DIS-ORDERLY NURSE
by Rumple Foreskin

* Donna Faircloth, newly minted nurse and young wife, was getting gloriously fucked. Waves of ecstasy surged through her writhing body as the powerfully built man lying between her widespread legs hammered his demanding cock in and out of her very willing cunt.

She'd enjoyed this sort of erotic bliss many times since her wedding, but tonight was different. This incomparable lover wasn't her husband, Clay. At the moment, he was home with no idea where she was, what she was doing or who she was doing it with. 
   
But Donna knew. God, but did she know. Panting with passion, she lay on the backseat of an old car parked in a dark, deserted alley near her hospital being screwed senseless by a handsome, charming, black orderly named, Malcolm Johnson.
   
For just a moment, she wondered if Clay would care if he did know. But then her body began to tremble and her skin flushed as this new lover's deep, rhythmic thrusts started pushing her towards another orgasm, and she forgot about her husband and everything else.
   
It wasn't the first time a man other than her husband had his cock stuffed deep inside her pussy. But unlike her previous experiences, this wasn't part of some wife swap or a threesome with Clay and one of his Army buddies. This was her first taste of adultery, her first experience with cheating, the first time she'd ever being unfaithful, and Donna was loving every illicit, erotic moment.

Before neeting Clay, her sex life had been limited to periodic couplings with her long-time fiancé. While that had been okay, sex seemed more like an obligation than a pleasure.

Clay taught her to enjoy making love and introduced her to many marvelous variations. Over the last few weeks however, their sex life had been going downhill. The situation had become so bad it seemed like neither of them was ever interested in sex—at least not at the same time. 
 
She still wasn't sure if the problem was due to her promotion or Clay's tough schedule this semester. Maybe it was both. She'd recently become the ward's evening shift supervisor and felt driven to do the job right. It meant she sometimes came in from the hospital too tired for anything but sleep. Even when she did feel like partying, Clay often seemed unenthusiastic. To her  astonishment, he even begged off a couple of times, claiming he had to study.
 
Tension, fueled by Clay's attitude, plus her increased workload and growing horniness, began to build until they got into a big fight last weekend. It had started over nothing but didn't seem close to ending.
 
Then earlier this evening, Malcolm made a pass at her. The charming, good-looking, pre-med student worked on her unit as an orderly. From his first day on the job, she found herself drawn to the tall, muscular, ex-football player.
 
With enough interests in common to make conversation easy, she and Malcolm quickly became good friends. He and his attractive wife even came to a couple of her parties. With her slim, stylish figure, high cheekbones and glowing brown skin, just standing beside her made Donna feel pale and dumpy. Still, she tried to make friends with the part-time model, but Malcolm's wife proved to be as cold and aloof as he was warm and outgoing.
 
Knowing about his wife's great looks made Donna feel comfortable with the flirting and teasing which quickly became a regular part of their friendship. Many people, including Malcolm, said she had a sexy body, "bedroom" eyes, and kept raving about her long legs. But having been a chunky kid, she could never think of herself as being attractive, much less sexy. So now she found it hard to believe that Malcolm, with his great looking wife, actually wanted her.

At one time or another, she had caught herself speculating on what it might be like to actually make love with the slim-hipped, broad-shouldered orderly. But she never considered doing anything more than just daydreaming about sex with Malcolm, especially without Clay's knowledge or presence. 
 
Then Malcolm hit on her. At first she thought he must be teasing. But the look in his eyes made it clear he wasn't. To her amazement, this good-looking guy with the great looking wife was serious when he said he wanted to make it with her. The realization sent her emotions reeling from startled, to intrigued, to aroused 
 
While Donna knew she should say no, she was mad at Clay, horny as hell, and suddenly very turned on by this sexy man with the big smile and beautiful, dark brown skin wanting her. So instead of laughing off his proposition, she hesitated for a long time and then heard herself accepting his proposal.
 
Now the shift was over and they were parked in a dark, deserted ally somewhere near the hospital making love in the back seat of his old Chevy. She could have cared less about the exact time or their exact location. Laying on her back, free of clothes and inhibitions, with her arms wrapped around her lover's back and a smile of erotic joy on her face, Donna had her entire being focused on the here and now. 
 
The car rocked slightly as Malcolm rhythmically drove his unyielding dick in and out of her flushed, tingling flesh. Waves of ecstasy raced from her churning, stuffed cunt out to every cell of her tingling body. It was such a fabulous fuck, she'd completely forgotten about the seemingly endless wait she had endured during the hours before it finally started.
 
After accepting Malcolm's proposition, it seemed like work would never end. Second thoughts battled with erotic thoughts up to the last moment. Even when they made hurried plans for meeting after work, Donna remained uncertain if she would have the nerve to really go through with it. 
 
When the shift finally ended, Malcolm walked into the nurse's station as she was getting ready to leave. "See you later, Lady," he said with a casual smile. 
 
It may have sounded like an innocent good bye to the others milling around during the shift change, but she knew he was asking whether she still wanted to meet him after work. Suddenly, she couldn't move, talk, or think. Her heart was racing, her legs were trembling, and her mind had gone blank. After taking a deep breath she smiled and, in a voice she hoped sounded normal, gave the signal that she would be waiting for him. "See you soon, Malcolm." 
 
Just to be sure there was no misunderstanding, she stopped beside him on her way out and while pretending to be searching for her keys whispered, "Real soon, I hope."
 
To avoid arousing any suspicions, they had decided she would leave first. He'd then follow a few minutes later. They would meet in the parking lot of a dingy, out of the way, diner in another part of town. With her anxiety and excitement growing by the second, Donna drove quickly to the rendezvous spot and pulled into the dark, half-deserted parking lot.
 
As Malcolm had suggested, she stayed in her car and waited, with nervous impatience, for his arrival. She felt horny and scared and turned-on and guilty. Even though she had already called and told Clay she'd be working late, she knew there was still time to change her mind. Despite all the second thoughts, however, once Donna left work, she never seriously considered backing out.

This was, she realized, something she really wanted to do and, as she had whispered to Malcolm, she wanted to do it real soon. Where they would go to do it didn't matter. That was his worry, not hers. All she wanted was to have her arms and legs wrapped around his strong, sexy body while he filled her churning pussy.
 
A flash of headlights made her turn in time to see Malcolm pulling into the parking lot. The moment he stopped, she jumped out of her car, locked the door, and hopped in beside him on the front seat of his well-used '63 Chevy. "Glad you waited, lady," he said in a deep, sexy voice before leaning over and giving her a long, deep kiss. 
 
With the exception of a New Year's Eve kiss at a party, this was the first time their lips had met. To Donna's delight it was a good kiss-deep, searching, and erotic. She relished his sensuously musky taste and the feel of his tongue slowly probing into the intimate recesses of her mouth. When Malcolm broke the long, intense kiss, they stared into each other's eyes, wordlessly confirming their eagerness to turn desire into deeds. 
 
A big grin broke across his handsome, brown face and he shifted back behind the steering wheel. For the moment, Donna remained motionless, transfixed by the eroticism of the kiss. When he glanced back, the look of approval and lust in his eyes made her shiver with anticipation and pleasure. 
 
It seemed unreal that her body could stir such emotions in this man or that it would soon be exposed and taken by him. As her skin tingled with excitement, Malcolm squeezed her knee, then slipped his hand up to the hem of her uniform's short, white uniform. After a last, gentle caress, he shifted gears and quickly drove out of the parking lot.
 
While her skin continued to tingle with excitement, Donna ran the tip of her tongue over her lips, enjoying the faint taste left by Malcolm's kiss. She watched as he sped through the late hour traffic. This wasn't some teenage date they were on, she thought, and they sure weren't going parking, at least not in the usual sense. It wouldn't be just another end of the date make-out session with the guy trying to seduce her. After all, she had already been seduced. Now she was about to get fucked. 
 
It was around midnight and this good looking, black hunk was taking her to some unknown place. Both knew what would happen when they arrived in just a few more minutes. She would be naked on the backseat waiting for him to see, touch, maybe even taste, and then take her. It was an incredibly arousing thought that left her pussy soaked and her body shivering with excitement.
 
Donna had no idea how much further they had to go; she just hoped they'd get there soon. It occurred to her that since she'd already been seduced and both knew what was about to happen, there was no need to play coy or hard to get. Why not, she decided, go ahead and get ready instead of waiting to arrive at where ever they were going?
 
Once she'd slipped off her white shoes, Donna lifted her hips, hiked up her skirt, hooked her thumbs inside the waistbands of both her panty hose and panties and quickly pushed them down her long legs to the floor.
 
After retrieving the panties and hose, she started stuffing them into her purse when the car swerved. She glanced over and saw Malcolm struggling to keep an eye on the road while staring at her lap. Following his gaze, she saw her skirt was still hiked up around her hips, giving him a great view of her legs and maybe even a little peek at her damp, curly, pubic hairs.
 
"Better watch where you're going," she teased.
 
"I'm trying to," he said. "But you're one hell of a distraction."
 
"Well here, maybe you won't be so distracted if you keep these for me." With a self-satisfied smile, she reached over and handed him her panties. They were still warm from her body and damp from her juices. Seeing how the present made his distraction even worse made her smile.

Unable to resist the temptation to toy with his obvious eagerness, she scooted closer and placed her lips against his ear. After gently caressing it with her tongue, she whispered, "I don't know where we're going, but like I said before, I hope we get there real soon,"
 
"Believe it or not, we're heading back toward the hospital," said Malcolm, as he fingered the damp spot on her silky panties. "It's actually a pretty safe area and I know a deserted alley were we'll have some privacy."
 
"That's great." She spoke in low and sultry voice while unzipping his pants. "Just hurry."
 
"Wheels don't fail me now!" exclaimed Malcolm, as she reached inside the open fly and wrapped her fingers around the thick shaft of his very hard cock.
 
Both of them laughed at his joke, but the laughter stopped when, after a brief struggle, she managed to pull out a long, thick, and very stiff dick. For just a moment she admired its size and color and hard warmth. A drop of pre-cum appeared on the purplish tip and she licked at it, savoring the salty taste, knowing more would soon be coming. Unable to resist any longer, she lowered her head and slipped the swollen cock head between her lips. 
 
They changed lanes a few times and even stopped at a couple of traffic lights, but she never stopped working her mouth up and down the length of the hard, ebony shaft. With slow, teasing movements she soon had Malcolm at the brink of erupting, but made sure he got no further.

The car made a sudden, sharp left turn, then slowed slightly before making another left turn. When Donna looked up, she saw they were in an alley.
 
"Are we there yet, daddy?" she asked with a giggle while licking on the big, sensitive cock head.
 
"Yes child," replied Malcolm, who had obviously found it almost impossible to pay attention to his driving during Donna's blowjob. "Thank heavens we're almost there."
 
After giving the swollen cock head a final swirl with her tongue, Donna released her grip on the thick shaft. With the car still moving, she climbed into the back seat and began pulling off the rest of her clothes. In part, her motivation was to have nothing interfere with the feel of Malcolm's body pressing against hers. But she also wanted to be sure Clay didn't catch her coming home in a badly wrinkled, semen stained uniform. It would be the last thought about her husband for a long, long time.
 
After hurriedly folding and putting her uniform on the rear window shelf, she stretched out on the worn fabric of the big back seat and propped her head on an armrest. With a smile of anticipation, she slowly spread her legs and then looked up at the back of Malcolm's head.
 
A shiver of excitement raced through her when he finished parking the car and killed the engine. After all these hours of waiting, it was finally about to happen.
 
As she thought about Malcolm lying on top of her, Donna began absentmindedly stroking one of her breasts and its hard, throbbing nipple. She noticed what she was doing, smiled to herself, and reached for her damp, matted pubic hairs. When she touched her moist, sensitive pussy lips, a jolt of sexual energy shot across her eager body.
 
After turning off the headlights, Malcolm turned down the car radio then pushed in the cigarette lighter. Donna knew he was trying to act cool. But I'm one incredibly horny woman, she thought, way more than hot and more than ready to trot.
 
Without looking back, he asked, "Want a smoke?"
 
"What do you think, Malcolm?" replied Donna, with what she hoped sounded like a low, sexy voice.
 
In response to her question, he turned his head and looked into the back. Donna's nude, alabaster body lay stretched out on the back seat, glowing faintly in the dim light from a distant street lamp. Her legs, lips, and eyelids were slightly parted. As she looked at him, one hand casually toyed with her dark blonde bush while the other caressed a most inviting boob.

The sight of Malcolm's mouth hanging open and the look of blatant desire on his face told her better than any words how much he liked the view. After waiting for him to say or do something, she cocked her head and gave him a coy smile.

"So tell me Malcolm, is a cigarette what you really want the most right now? I mean, if it is, well, that's okay with--." 
 
"Not only no, but hell no!" he shouted while vaulting over the back of the front seat and into her waiting arms. After a quick, hard kiss, he moved down and locked his lips around one of her hard nipples while feverishly ripping off his shirt and pushing down his pants. A few seconds later, his hard body pressed against her soft flesh while his unyielding cock pushed against the entrance to her willing pussy.
 
They kept kissing until he lifted his head, looked at her and smiled. She looked back through eyes clouded with lust as they lay body-to-body, motionless and expectant. Without warning, he hunched forward, ramming his cock deep into her with one powerful stroke. Donna gasped with pleasure and surprise as the engorged dick hurtled toward the depths of her tight cunt. Moments later, the final inches of his thick shaft sank past her stretched pussy lips and the big, flared, tan cock head slammed into the inner most recesses of her quivering body.

As she shuddered from the impact, her head jerked back and she let out a moan of delight. With their bodies now fused together, Malcolm paused and leaned over until their lips meet. As their tongues touched, his hips sprang into motion and he began fucking her eager body.
 
Donna's skin seemed to ignite with desire. The smooth, rhythmic motion of Malcolm's large cock head plunging in and out of the depths of her pussy quickly triggered the first in a series of small, intense orgasms that rocked her from tingling scalp down to curled toes. 
 
She gasped for breath and wrapped her arms around his broad back before grabbing onto the cheeks of his tight, well-muscled butt. It would tense and flex each time he made another long, fluid thrust into her churning cunt. 
 
Their bodies began to work in synchronized harmony. Instead of another mini-climax, a different, more intense sort of sensation started taking control. Spasms of electricity raced through her body. With one foot on the floorboard and the heel of her other pressing down on top of the back seat, she forced her hips up to meet his thrusts. The muscles in her vagina clinched around the long, thick, unyielding cock as her body began to jerk and shiver.
 
A sound of pure unbridled passion burst forth as her body exploded in a soul-shattering, mind-numbing climax. Her entire body became an extension of her pussy, and her pussy felt like molten passion. 
 
Moments later, Malcolm let out a grunt. Donna moaned with delight as she felt his pent-up sperm blasting deep inside her churning pussy, filling it to overflowing with warm, thick cum.  
 
"Un-fucking-real," he groaned. As the last tremors of his orgasm rolled away, Malcolm collapsed on top of her exhausted but very satisfied body. His hard, sweaty, body lay motionless and spent on top of hers.
 
As she gently stroked Malcolm's sweat-slick skin, Donna knew she had shared this amazing experience with someone very special. While she might still love her husband, she wanted, even needed more, much more, of this incredible lover, now and in other nights to come.

She squeezed her pussy, felt resistance from Malcolm's still stiff cock and smiled to herself. Still, there’s no time like the present to start getting some more.
 
#

The following week saw no change in the simmering feud between Donna and Clay. Any twinges of guilt were swept away by his crappy attitude. It made getting away with Malcolm for a repeat performance even more desirable. Setting it up proved harder than she had anticipated. Malcolm, who had some night classed, couldn't always work on her evening shift. Their both being married made things even tougher.

While Malcolm's wife might have fashion model good looks, she was still a jealous, suspicious woman. One evening, as they cooled off after a quick, and dangerous, kiss-and-grope session in the supply room, Malcolm admitted he wouldn't have come on to Donna if his wife hadn't been out of town. "Wouldn't be worth the chance," he explained. "I promise you she'd have come up with some excuse to call the unit to make certain I really was working late."

The last thing Donna worried about was Clay getting suspicious. However, he had been known to be super horny she got in from work and insist on their immediately making love, sometimes on the living room floor or even the kitchen table. In the past it almost never bothered Donna. In fact, she usually enjoyed his spontaneous outbursts of passion.

But now she worried it might happen on a night when she came in following an after-work session with Malcolm. That possibility bothered her all the way home the first time they made love. Fortunately, Clay had been asleep that night. But it could happen. That concern, coupled with Malcolm's jealous wife, made scheduling a repeat performance a real challenge.

To Donna, it seemed like a long time coming, but things finally fell their way. Both had duty on an upcoming Saturday evening. Earlier that week, during a break at work, Malcolm said his wife would be out of town on a church choir trip. He suggested they get a motel room and use it both before and after work. It seemed like a great plan.

She told Clay she wanted to check out some of the new stores near the hospital before going into work. As she'd expected, and hoped, he turned down her invitation to get up early on Saturday morning and go shopping with her. Then she said that to save the drive back and forth, she'd just take along her uniform and go straight to work and change there.

It seemed like Saturday would never come. With each passing day, her excitement mounted. Once it arrived, however, the day proved more than worth the wait. To her utter delight, it would be a long, exhilarating, unforgettable day filled with incredible sex.

The moment Malcolm finished locking the motel room door they fell into each other's arms. Still just inside the door, they kissed hungrily and tore at each other's clothes. As the last piece of clothing fell to floor, he cradled her in his arms and carried her to the bed where they made wild, passionate, uninhibited love.

When the exhausted Malcolm finally rolled off the well fucked but exhilarated Donna, she knelt on the bed, leaned over his sweaty, panting body and popped his cock into her mouth. She wanted to taste the residue of their lovemaking that still clung to his dark phallus and hoped she'd soon feel the now semi-erect shaft stiffen inside her mouth. Her ultimate goal was to use that re-invigorated rod for at least one more round of serious sex before they had to leave for work.

In its present condition, she could take the entire cock into her mouth. The thick coating of cum and her own pussy juice covering the shaft quickly yielded to her lips and tongue. Then she switched from cleaning to sucking. To her delight, the smooth head soon began to swell and fill her mouth. Donna felt the familiar, excited churning in her stomach at the thought of all the pleasure she knew this big, brown, baton was about to deliver.

Unable to control her excitement, she wiggled her ass and heard herself moan with anticipation. The thick, dark pole slid in and out of her warm, wet mouth while her fingers gently massage Malcolm's huge balls.

Mesmerized, Donna watched the dark-brown shaft plunging in and out of her mouth. It suddenly occurred to her that chocolate had always been her favorite flavor and she almost gagged while trying not to laugh.

Removing the now stiff cock from her mouth, she slowly ran her tongue up the length of the shaft. After circling her tongue around the smooth, flared head, she gently slid it past her lips and teeth, then quickly filled her mouth with the dark, delicious pole and resumed her skillful sucking.

It wouldn't be long she knew, before Malcolm would be wanting to once again bury his chocolate delight back inside her cum drenched and pulsating pussy. She also wanted that, of course, and soon. But for the moment, she was perfectly content to keep on licking and sucking on his marvelous cock while waiting on him to start slamming this long, hard tab back into her slippery slot.

It wasn't a long wait.

When they finally got to work, it proved to be a typical, slow Saturday on the unit with just enough activity to keep them out of the supply room. Shortly after the patient's had their last meds and been bedded down for the night, Donna got a call to send the relief aide to another ward.

No evening supervisor could have ever been happier to oblige. With the aide gone, she and Malcolm would be alone the rest of the evening.

The aide had barely left before Malcolm began coaxing her to join him inside the adjacent supply room in the back of the nurse's station. Although acting reluctant, she soon yielded to his insistent urgings, assuming he wanted a quick make out session.

Almost no one came around on weekends and the patients were asleep. With the aide gone, they were probably safe. So Donna decided a little foreplay before resuming their lovemaking after work would be okay, and fun.

To her surprise, once they were inside the supply room, Malcolm had her sit down on an armless, straight-back chair facing away from the open door to the nurse's station. Moving around in front of her, he unzipped his uniform, pulled out a very erect penis, and pointed its swollen, purple-hued tip directly toward her lips.

"The only thing I've been able to think about this entire shift is how great it felt when you were going down on me this morning. That's why, as you may have noticed, I've been afflicted with this boner all shift," he said with a smile.

Donna had noticed, of course. How could she have helped but notice? Especially, after he slipped behind her back during a brief lull before supper. As she'd leaned forward looking for something on the desk, he surprised her by grabbing her hips and pressing that big, hard bulge in his pants against the thin, white fabric covering her rear.

"So since you're kinda responsible for this condition," he said, first teasing, and then coaxing, "won't you please give me another serving of your righteous lip loving and relieve my strain?"

This was not what she wanted to do, at least not here and now. It was one thing to run the risk when they had no choice. But a room and big bed were now waiting for them. Once there, she'd be more than happy to oblige him, but not now, not here.

Just as she was about to object, Donna looked up and saw Malcolm staring down at her with obvious passion and need in his dark, brown eyes. After seeing that look, there was no way she could refuse. With a wink that belied her uneasiness, she said, "Okay, but keep an eye out in case someone comes."

"Don't worry, Lady, I'm the only one who's gonna be coming around here," he said, with a big, pleased grin.

She shook her head in mock despair, and then took his long, rigid pole in her hands, leaned forward, and began giving him a very nervous blowjob. As her lips encircled his swollen and sensitive cockhead, he sighed and shivers with pleasure. While nibbling on the shaft, she took a quick peek up at his face. To her relief, his eyes were open and he seemed alert for any call lights, unexpected visitors, or wandering patients.

Just as she sensed Malcolm was about to come, he pulled her up and turned both she and the chair around. Then ignoring her confused protests, he shoved hard against her back until she had no choice but to lean over the back of the chair.

With a sense of both fear and excitement, she realized what was about to happen. She also realized that short of creating a major scene, there was no way she could stop it from happening. After yanking up the short skirt of her white nurse's uniform, he tugged  down her white panty hose. When he noticed she wasn't wearing any panties, Malcolm murmured, "God, but that's just the way I like it," in a voice choked with passion. Moments later, he ripped off her shoes and tossed them and her panty hose aside.

For Donna, it wasn't a comfortable position, especially when Malcolm spread her legs to the max. But she felt nothing but a thrilling sense of danger and intense erotic anticipation. She gasped in surprise when he roughly grabbed the cheeks of her ass and pulled them apart.

Helpless, nervous, and expectant, all she could do was stare out the door. She heard a low, guttural groan and sensed him lunging forward. Moments later, the swollen cock slammed into her eager pussy and raced toward the innermost reaches of her stunned body.

After that first, breath-taking shock, it became a fast, hard, and very deep fuck. Any worries about getting caught vanished. Nothing mattered except the exquisite feel of Malcolm's powerful cock sinking up to the hilt each time he plunged it back into her quivering pussy.

When it ended, she lay slumped forward over the chair with her rubbery legs. Her warm bottom pointed toward the ceiling. Malcolm's thick semen and magnificent manhood filled her tingling pussy. She was breathless and trembling from the intense, final orgasm that ripped through her body moments after he made one last savage thrust and deposited another load of his warm seed deep inside her convulsing pussy.

In the midst of this post-coital bliss, the phone began to ring. A frantic struggle followed to disconnect from Malcolm and stand up. After quickly pulling her skirt down, she hurried barefooted from the supply room to answer the phone. It was, of course, on the other side of the nurse's station.

To her surprise, the call was from Clay who wanted to know where to find some index cards. While struggling to keep her voice calm, she told him where to find them and then said she'd be working late that night. He sounded disappointed at the news.

After a short pause, he said, "Donna, I love you. I'm sorry I've been such a bastard about your job and all. Maybe I'm jealous of it, or worried it might come between us. And I guess, mostly because of me, it kinda has. Anyway, wake me when you get home and let's talk, okay?"

Clay’s words, his emotions, the tone of his voice, they all sounded sincere. Maybe things would get better between them. But things could never be the same. For the first time, she felt more worldly, more knowing than her husband.

He’d never know she'd be working late, but it’d be on another man's cock in a motel room on the other side of town. Nor would he ever imagine his unexpected call had interrupted her post-sex reverie, forcing her to disengage from her new lover and hurry barefooted to the phone. And he would never, must never, know that she could see this lover smiling at her and touching his flaccid but still meaty cock that glistened with his cum and her pussy juice.

And Donna was sure Clay would never suspect that while they'd been talking, she could feel the thick semen syrup that same dark cock had deposited deep inside her body ooze past the swollen lips of her tingling, freshly fucked pussy and slowly trickle down her long, trembling legs.

But Donna knew it all, and that she'd soon be doing it again. After Clay’s call, however, she also knew she still loved her husband. “Goodnight, honey. Don’t wait up for me. We can talk tomorrow.”

As she hung up the phone, it occurred to Donna that her life was about to become very interesting.

==

Comments on this story and its twin, Dis-Orderly Orderly, will be appreciated. rf