I heard it open and close again, our seldom-used back door. I unlock it every morning after everyone else leaves for the day and before I head into my home office to start working.

I know who and who it is, and my dick starts to get hard. I get up from my desk and move toward the stairs, and from there, I can hear heavy kissing and light giggling. I reach down and adjust my rapidly swelling cock inside my jeans. 

The giggling quickly turns into low moans, both male and female tones. I slowly take the steps one by one up to the next level and peek around the doorway. From the other side of the kitchen island, I can see a college-aged, well-built guy facing me and a head of burning red hair bouncing near his crotch. It was my daughter's friend Anna sucking off her boyfriend Eli, and damn, she is enjoying it.

So, a bit of a backstory before moving forward. Anna has been my daughter's best friend for years. The other night we were having a pool party, and I caught the two of them fucking in a spare bedroom. My presence didn't seem to faze them, and with their young and oversexualized personalities, they kept going at it. My voyeur side grabbed hold of me, and I couldn't bring myself to tell them to stop, but I was also frozen in shock and unable to leave either.

Anna was straddled over Eli, with her bikini top still on, with one very ample tit fully exposed, and her bottoms pushed to the side. She caught a glimpse of me yet remained unfazed and maintained her rhythm. She shot me a sinister wink and devilish lick of her lips before lowering herself down and grinding him to completion.  

Anna and Eli returned to the party but soon left without much conversation.

Anna stopped by the house a few days later to drop off something. My daughter wasn't home, so I offered to help her. I wanted to clear the air at the car, so I joked, "So...you and Eli the other night…that was pretty bold." 

She blushed and said, "Yea, sorry about that. Since all this Covid crap happened, both our parents are working from home now, and we can't get any time to… well, you know. It's killing us." She continued, "Thanks for being cool about it."

She then hopped into her car and left. I assume she didn't want to make it more awkward between us.

My head swirled over the next few days, filled with the sight of her twenty-year-old body grinding over him. Her full, beautiful breasts, that devilish look she shot me, knowing I was watching them. And then it hit me, the solution to their parents stifling their sex time. I also work from home, but my wife does not. I could provide a safe place for them. I was young and horny once too. I remember what it was like sneaking around, trying to find a few minutes for a quick fuck.

A few nights later, only the girls were at our house again. I was looking for an opportunity to get a few minutes alone with Anna to tell her about my idea, but it was tough. I was inside wiping down some dishes when she entered to use the restroom. We exchanged smiles, and I immediately slowed the cleaning, hoping to be there when she returned.

"Hey Anna," I said, "got a minute?" as she walked back through the kitchen.

"Sure thing, Mr. G.," she replied.

I turned to her with the kitchen island between us, "I've been thinking a lot about your, um, 'situation' with Eli."

She cocked her head and, with a sly smile, said, "Oh, have you been?" She may have taken my statement out of context, but she saw me there watching them, so she was perfectly justified in thinking it.

I shook my head and continued, "No. Well, yes… but no. Whatever, I might have a solution for you."

"Go on." She said under her breath as she shifted her weight and placed a hand on each of her hips.

With that, another friend came in, and I quickly changed the topic, "So you and Eli are both staying home for college again in the fall?" It was a quick conversation turn, but still, some information I needed to know.

"Yea, we have two more semesters left here, and then who knows?" She replied, picking up on the diversion.

Thankfully the friend went back outside quickly. My tone changed back to sound more undercover. "Perfect," I replied. "If you are both staying home for school and can't do it at home, then do it here."

She shook her head in disbelief, doubting what she heard. "Wha… what?" she questioned.

"We are close to campus... Dawn isn't home, and Kathy will be away. I'm in the basement office, usually blasting music so loud a bomb could go off without me knowing." I paused briefly to let the idea breathe. "I can leave the back door unlocked for you; use the guest bedroom—no one goes in there anyway—just make sure you don't leave anything behind and straighten up."

Her eyes showed a mix of surprise and confusion.

"Listen, I was young once too… I get it." I reassured her.

She recomposed herself and turned to lean on another countertop. Looking back at me, "And what about you?" she questioned, raising her chin.

"I'll be in the office downstairs. I won't know a thing. I promise." I assured her. "Besides, the back door isn't in view of the security camera, so if you go up through the side yard, no one will know."

Her face changed, taking on a more stern, inquiring look, "Well, you certainly seemed to enjoy yourself the last time…"

I threw my hands in front of me to stop her mid-sentence, "That was a mistake. I'm sorry; I was frozen in the moment. I honestly wasn't…"

She cut me off, dropping her face into a more relaxed position, "Nah, it was kinda hot." Smiling as she said it.

My cock jumped at the phrase. She turned toward the back door and said, "Let me talk to Eli," as she walked out without another word. I couldn't help but stare at her perfect ass, with just enough of a pinch of cheek poking out from below her insanely high shorts before she disappeared out the door.

The event broke up shortly after, and nothing more was said about the idea.

The new semester started about a week or so ago. My daughter was away at college again, and my wife was back at work. I figured that Anna had passed on my suggestion. That is until I got this text, "Your idea…. OK, how do we do this?"

I looked at it for a minute. I tapped out and deleted three replies before typing, "Tomorrow morning I will unlock the back door for u." I hit return and thought about it for a second. I followed with, "Come over whenever btwn 9 and 2. Dawn gets home by 3." 

However, before I could press send on that line, I got this reply, "Tmrrw? Now OK???" with a pair of praying hand emojis, immediately followed by, "pls?" 

I deleted the last line and replied, "Sure, door unlocked."

I sprinted up the stairs to the back door faster than I ever thought I could, unlocking it and pausing to catch my breath. I'll admit that the whole way up, my mind pictured the sight I had seen a few weeks earlier, making me very stiff.

I returned to my downstairs office but lurked at the bottom of the stairs listening for any sounds. Within a few minutes, I heard the door open and quietly close, followed by a few "Shhhhh" sounds and some soft giggling. I couldn't hear any more as they must have made their way to the second-floor guest room, as we initially agreed. I couldn't bring myself to leave that spot. I reach down to adjust my now throbbing cock. I thought to myself, "I wonder what she was wearing? A skirt? Tight jeans? Was he fucking her doggie or missionary? Oh, maybe they are 69'ing?" Each scenario flashed visions inside my head, blending and morphing with each other as if they were really in there. The pull on my jeans became tighter. 

Adrift in my imagination, I lost track of how long they were up there. My mental fantasies were disrupted by the sound of feet softly running down the main staircase and that same door closing again. I waited a few short minutes, but my curiosity couldn't be contained. I bolted upstairs and into the guest room.

They had straightened the bedsheets to where they were before; to anyone else, it would appear no one had been there. I took a deep, long whiff of the room, and I could smell the sex, making my mind flip and my body shiver. I pulled back the top sheets, and to my delight, I saw a small wet spot slightly off-center on the bottom sheet. I immediately unbuckled my jeans and started masturbating. I couldn't control myself. I put my hand next to the spot, feeling a slight warmth, and then dropped my face next to it. Knowing that her perfect ass cheeks touched these sheets and her young pussy was pounded right here drove me to an uncontrollable lust. I don't know what came over me, but I turned my head and began licking the wet spot. It had little taste; most of it had already soaked into the fabric, but I could feel a slight wetness on my tongue, and the very thought of that being straight from Anna's pussy made me cum almost instantly and hard.

I had to catch my spunk with my other hand. After all the care taken to conceal the rendezvous, I couldn't risk staining the sheets with my jizz. I shot a sticky white load into my cupped hand, and it began to drip through my fingers. With no time to enjoy my orgasm, I rushed into the bathroom to clean up. I composed myself, buttoned up, and returned to the room to re-fix the sheets. Looking at the spot again, I bent over and pushed my face into it once more, this time harder than before, and sucked in with my nose and mouth, hoping for any hint of her fragrance to carry me through the rest of the day.

Back on my desk was my phone, with a single notification lighting up the screen. It was from Anna and said, "TY" with a heart emoji.

I replied, "NP," and left it at that.

Each morning after that, I unlocked the door and spent the day listening carefully, but no one came.

A little over a week after that first incident, I was in the kitchen making lunch when the sound of that door opening broke the silence. I quickly knelt behind the island. I couldn't see them but heard the unmistakable sound of high heels clacking across the hardwood floors. As a closeted foot fetishist, that sound turns me on beyond belief. My mind began racing again; I wondered what style they were, how tall, does she keep them on while fucking? The clacking sound got fainter as they moved toward the upstairs hall toward the back of the house. I couldn't move; I just knelt there, pondering what was happening upstairs. I found myself wondering about how smooth her ass and legs were? How her full tits must look, bouncing with every thrust? And also fondly remembering that wet spot, fantasizing about how amazing her pussy must really taste like?

I never viewed my daughter's friends in a sexual manner. However, Anna had grown into an incredibly attractive woman after graduating. She was tall, standing about 5 foot 7ish without heels, most of it her legs. Her face was soft, round, and with plump, pouty lips. She grew to a solid C-cup and had a body perfectly shaped by years of dance classes and playing volleyball. And right now, she was getting fucked in my house!

I quietly moved from behind the island to the bottom of the stairs. From there, I could hear the louder sounds and moans… boy they were surely going at it! My heart rate increased as I slowly climbed the staircase, one step at a time. I kept telling myself this was so wrong, but my deviant mind rejected any thought of stopping. I got to the top of the stairs and heard moaning, grunting, and bodies slapping against each other. They were a very talkative couple, injecting "harder baby" or "fuck you feel so good" in between their primal sounds. I got about halfway down the hall, and my boner felt stretched to its limit.

I stood against the hallway wall, my heart racing, pants budging, and trying to breathe as quietly as I could. As I heard them begin to climax, I reversed my direction and quickly descended both flights of stairs and back to my office. I have no idea exactly when they left, but I gave them a good hour before checking to see if they were gone. I lifted the sheet, but there was no wet spot this time, which made my mind jump into visions of Anne on all fours and Eli giving it to her doggie style. Immediately my hand went to my belt, ripped it open, and dropped my jeans so I could masturbate to my imaginary replay of what may have just happened here.

I guess they must have grown more comfortable with the situation because they stopped by five times over the next two weeks. Sometimes I would force myself to stay in my office, but more often than not, I felt helplessly drawn upstairs to eavesdrop. With each rendezvous, I inched closer and closer to the door until this last one, where I was right outside the door jamb. I could faintly smell the sex emanating from the room. After each session, I would scamper back to my office and wait for them to leave, only to return to the room, drop my pants, and jerk off.

After their latest tryst, I retreated to my office to wait them out. Shortly after, my phone lights up with a text from Anne, "Don't be so shy nxt time."

My heart skipped a few beats as I processed the idea that I might have gotten caught and that my spying skills may not have been as stealthily as I thought.

As I'm processing this, a second line of text pops in below that one that reads, "btw, :gift box emoji: 4u under pillow."

With a thud, I drop the phone on the desk and race upstairs, throwing the decorative pillows off the bed. There sitting under one of them, was a lacey pair of purple panties. I pause briefly to take in the sight of them. They had a thick band across the hip area, a triangle shape in the front that slimmed down to a tiny g-string in the rear. They were adorned with matching purple lace up the front and over the sides.

I grab them, feeling the delicate lace between my fingers. Without hesitation, I pressed them to my face and inhaled a deep whiff of them. It was heavenly. I could imagine her still in them. A soft drip of liquid traced my knuckle, "My god, these are soaked," I said under my breath. Kneading them in my palm, I pressed the wetness into my hand. I felt a thick drop of precum fill my underwear, and I wasn't even touching myself.

I grabbed some of the lace with my other hand and stretched them wider. My thumb and forefinger slid to the crotch area and were immediately covered in a lubricated substance. I stared at the crotch area as if I could burn a hole through it and, in one motion, pushed my tongue into the moist fabric. It was so wet and juicy. I lapped it up while dropping my other hand down my pants, which at this point were equally soaked. I didn't care if the juices were all Anna's or a mix of hers and Eli's, but this patch of material, this tiny strip of soaked panty, touched Anna's pussy, rubbed on it… and she came in them. My hand gripped my cock so hard, and I jerked off more furiously than ever before, exploding in my pants as I licked and sniffed this soft purple treasure.

That night, I made up some excuse to return to work after dinner, exaggerating a deadline. But really, I only wanted to get another chance to worship those panties. I put them in a sealed bag and hid them in a filing drawer. All day I tried to reply to Anna, but there were no words I could think of that said, "Thank you for the used panties." Or, "How did you know I was peeping on you and Eli?" Or also, "What did you mean by don't be so shy?" But I couldn't find the right words.

The following day, Anna sent another text; it was simply the purple heart emoji and the lipstick kiss lips emoji, nothing else.

I stared at it for over an hour, trying to formulate a coherent response. Eventually, I typed out, "TY. That was quite a surprise." and hit send.

The phone screen stayed motionless for what seemed like an eternity. My eyes locked on it. Finally, those three animated dots broke the visual silence.

The dots soon changed to this simple phrase, "I know."

Nothing was said after that, and I couldn't find the proper response, so I spent the rest of my day watching porn with one hand on my cock and the other pressing those panties to my face again.

Friday came, and I was in a Zoom meeting with a client when my phone lit up. I looked at it to see a text from Anna. I read it three times, completely losing focus on the meeting.

It was a picture of the old side chair that we kept in the guest room, followed by the text, "Go sit here….NOW"

I don't know if I hid the shock from my client, but I fumbled out some excuse for leaving the meeting and immediately disconnected. I honestly don't even remember what I said. I ran upstairs to the main level and looked around. No signs of anyone here, and I don't hear anything from upstairs. I raced up to the second level and into the guest bedroom. Nope, nobody here either. I saw the chair from the photo in the corner of the room and sat in it.

The house was silent as I sat there. Five minutes went by, then ten. The only sounds are the occasional cars passing outside until I hear the sound of the back door opening and closing. My body stiffens, as does my cock. I hear the heels clicking, getting closer. Each of my heartbeats seemed timed with her heel-clicking steps, growing in sound and intensity. My veins feel like they are going to burst through my skin.

Anna turned the corner and stood in the doorway. She wore what looked like a black-colored men's dress shirt but with wide billowing sleeves on her arms. The outfit turned into a knee-length free-flowing skirt below a golden belt buckled around her thin waist. The top was unbuttoned and opened down to the belt, exposing ample skin, some gold necklaces, and her symmetrical cleavage. I couldn't help but look down to find her long legs bare and lotioned to a shine. She wore a pair of matching tall black heels on her feet, primarily open except for a thick strap just behind her toes and then crossed over her ankle and tied in the back.

"Anna," I blurted out.

"Shhhhhh," she hissed from between her deep red lips. "Just sit there and relax, Mr. G." she followed with a sly smile.

With that, Eli entered, and they began kissing passionately. His hands went directly to her round ass, lifting her skirt. I could see that she wasn't wearing any panties today. My whole body tensed at the sight unfolding in front of me. Somehow, his pants ended up down and around his ankles, but I must have been so transfixed on Anna's ass to notice. She opened his shirt and traced her hands over his athletic chest; Oh, to be twenty again.

Anna slowly slid down to her knees and curled her fingers inside the waistband of his designer-brand boxers. With one motion, she pulled them down to his knees, and I watched as his cock sprang out of them. I'm generally not interested in guys' equipment, but Eli was impressive. It hung out from him like an elephant's trunk. I was too far away to tell, but it seemed very girthy, with thick veins wrapping around it. Anna's expression was one of excited pleasure as if she was seeing it for the first time, however we know that wasn't true. But with a cock like that, I guess every time it is presented, she is in erotic awe.

She took it in both hands and leaned in to wrap her red lips around it. I watched as she swallowed it inch by inch. As she neared his base, her hands moved up and over his chest, feeling each ab ripple and swollen pectoral muscle. She sucked on him hands-free, with her arms held straight up and on his chest, and her eyes locked with his the whole time. My god, this girl knew what she was doing. She pulled back, and with a wet pop, his cock exited her mouth. She took it in one hand, shifted her weight onto one knee, and turned toward me. My body almost melted the instant her eyes locked onto mine. She licked her glistening lips and returned to worshiping Eli's cock with her mouth. Her lips wrapped around the side and slid them over his whole length, all while keeping her gaze transfixed on me.

My cock was trying to burst through my pants; I don't think I've ever been this hard. I couldn't look down but could feel the precum welling and moistening my boxers. Anna stood up and crawled onto the bed on her hands and knees. Not missing a beat, Eli stepped behind her and threw her skirt up to showcase her heart-shaped bottom.

He rubbed it a few times and lustfully examined her backside while Anna positioned herself to be looking directly at me. Her assertive and seductive expression changed to one of pleasurable ecstasy as Eli pushed his massive cock inside her. As he stretched that tight young pussy, her mouth gaped wide open, and her eyes rolled upward. Eli tunneled each inch of his cock deep inside her, and her body responded in kind.

Her breathing froze momentarily, only to be broken by a low guttural moan. "Fuuuuuck….damn baby!" emerged from someplace deep inside of this woman.

Eli matched with a primal noise of his own just before her whole body started bouncing. Beginning slowly, Eli dragged his cock out of her pussy and thrust it back in again, each time quickening his pace. Her huge tits shook free from inside the button-down shirt and bobbed in tight circles with each thrust. From this position, I could see them hanging straight down and rounded to a point where her darkened nipples were fully erect. I could hear the sound of skin slapping skin as Eli drove his cock straight through Anna.

They volleyed each other's dirty talk with raunchier and dirtier statements than the previous.

"Fuck that pussy raw," Anna commanded.

Eli responded with calls of "Slut," and "Whore." The degrading conversation carried on like that between deep groaning and heavy breathing.

By now, I was visibly sweating through my Oxford shirt. I could feel the moisture building up all over my body. I was too stunned to move as my cock tried to rip through its denim prison like the Hulk. My fingers embedded themselves in the fabric of the chair's arms.

Anna threw her head up, whipping her hair backward, and looked at me dead in the face. Her gaze shot through my soul as she smiled an arrogant smile, biting her lower lip and scrunching up her nose, showing me that she knew she was pushing my mind and loins harder than Eli was driving her.

Eli reached forward and grabbed a handful of the hair she threw back and tugged, ripping her head back further. Her self-assured smile turned into a submissive gape, and her dementor transformed into a sluttier one as her lover tugged forcibly on that red mane.

"Ohhhhh, Baby," Anna whined. "Fuck me, Daddy," she now pleaded in a higher-toned voice.

Eli continued to assault her pussy, while also slapping her ass as she begged for it harder and harder with each labored breath. He gave a hard tug on her hair one last time, and she dismounted her position. Spinning around on the bed, she immediately took his cock in her mouth once again. I watched from behind as her head bobbed up and down furiously. Eli threw his head back and placed both hands tightly on her head.

I could hear him grunting and knew he was filling her mouth with his young cum. His shoulders raised and slumped as she milked him with her lips. I couldn't see it happen, but I heard her make a slurping sound as her face came off of his member. He relaxed his hands, and she gently giggled in post-coital bliss.

She stood up and turned toward me; I was frozen in place. With a slow strut, she walked toward me, still in her heels and huge breasts hanging out of her shirt. She locked in on my eyes and didn't break eye contact the whole way. A determined and focused look hung on her face, with her only other motion was to use her pinky finger to wipe away some dripping saliva from the side of her lips. She stood before me, making me look up, and it felt like she was a giant towering over me.

She threw one leg over my forearm, where I had a death grip on the arm of the chair. Bending her other leg, she slid it into the pocket between my hip and the inside of the opposite chair arm. She rocked her hips forward, and I could feel the leg of my pants dampening from her drenched pussy. I looked down in shock as she dragged her freshly fucked pussy over my thigh.

Soon her face came inches from mine, and we stared at each other motionless. Her eyes were thin and piercing, while mine were wide and in awe. With one swift move, she grabbed the back of my head and pulled me into her for an unexpected snowball kiss.

My eyes widened even further as she plunged her tongue between my lips and swirled Eli's cum directly into my dry mouth. I made some muffled sounds in protest, but Anna held on tight as her tongue probed my mouth and transferred the warm, thick load between us. I gagged on the saltiness and overall consistency of it. I have never tasted sperm before… what the fuck is happening? Once his jizz was fully transferred, she pulled off of me and cupped my face in her hands. She smiled a wide grin as light glistened off her damp lips. I was overcome with the onslaught of this mental sexual exploitation that I slumped back in the chair.

Without a word, Anna bounced from my lap and returned to Eli. I stared motionless at her perfect ass swayed from side to side as she walked away. The two locked hands and left the room, with Anna turning her head and shooting me one last seductive wink before disappearing down the hall.