That fall Caitlin’s brother Sean went off to college at Michigan State, leaving Cait and Megan with only each other to satisfy their desires – and me, of course. They had gotten such a kick out of dressing me up as a girl that they decided to do it again, and this time they would take me shopping for an outfit of my own.

As we strolled through the mall, it felt strange and exciting to feel the eyes of every boy tracking us with longing, to be one of three hotties on the prowl. I practiced my girly walk, imitating my sister Megan, with her liquid hips and languid posture, not Caitlin and her purposeful boyish strides, which I myself found equally sexy. I was curious to see what kind of clothes they would pick out for me, and quickly I realized that I was to be a schoolgirl Lolita.

We started with a padded bra and white cotton panties, then some pink hair-ties so they could put my hair in pigtails, then moved on to Mary Janes and tights. Finally, there was the classic plaid skirt, rather shorter than the nuns at, say, St. Agnes School for Wayward Girls would have liked, and a virginal white blouse. Of course, these last items had to be tried on, so we all crammed into the little changing room. It got pretty hot pretty fast in there, and it turned out the girls found the idea of my junk under a little skirt irresistible, constantly reaching under it to fondle my increasingly stiff penis. Of course, I found them equally enticing, especially Caitlin’s full breasts, which I squeezed and fondled under her turtleneck. I also loved watching the two girls kiss, seeing an occasional flick of pink tongue, and listening to their moans of pleasure. But we were worried about getting busted by the security cams, so we stopped short, and waited a minute for my skirt-bulge and Cait’s prominent nipples to subside.

We stopped in at the mall ladies’ room as I thought about all the times I had seen groups of girls head to the bathroom together and wondered what they got up to in there. The girls helped me complete my Lolita outfit, with the tights and pigtails and some more groping. Cait said she had to pee so Megan and I followed her into a stall and watched her unzip and lower her jeans, and saw the little yellow stream emerge from her crotch. Then Megan said, “Oh babe, you’re so hot, let’s switch places!” She sat on the seat, wrapped her hands around Cait’s firm little ass and drew her forward.

“Oong oung ooh!” Cait moaned as Megan began to lick her vulva. Her knees began to buckle and she reached out to steady herself against the wall. I squeezed in beside her, pulled up her shirt and bra, and began to nuzzle her lovely breast. I licked and sucked at her erect nipple and soft puffy areola. Then I stood up straight, kneading her breast and bringing my face close to hers, reveling in her heavy breathing. She gasped into my mouth as I kissed her, then again as I nibbled at her ear.

“Oh fuck fuck, suck me suck me baby, make me come all over your sweet face,” she encouraged Megan as she bore down on her eager mouth.

Hearing slurping sounds from below, I looked down and saw Megan’s head being pressed between Cait’s muscular thighs. She drew back for a moment and smiled up at me, and I saw that her face was shiny with Caitlin’s pussy juices. At this point I darted my tongue into Caitlin’s ear and also reached down between her ass cheeks, nudging at her puckered anus and working in the tip of my second finger. She squirmed and started to make the whiny, breathy sounds that I knew meant her orgasm.

“Ooh ooh eingngee eee!” she moaned and shuddered, then shuddered again and I had to try and hold her up as her whole body went limp with ecstasy.

“Oh my god oh fuck yes yes yes!” When she finally subsided, I helped lift her off Megan and the three of us kissed. I could taste Caitlin on Megan’s face, and Cait hugged both of us tight, beaming and thanking us as she always did, saying we were the best girlfriends she had ever had.

After we made ourselves presentable, we stopped for lunch, finding a booth in the back of a burger joint. I slid in and Megan slid in next to me, snuggling close the way gal pals are allowed to without anybody commenting. When it came time to order, the server seemed entranced especially by Megan, who smiled at him with her brilliant teeth and flashed her emerald eyes. When he tore his gaze away to ask for my order, I was surprised to feel a disturbance under the table. Cait had slipped off her shoe and slid her foot under my skirt, and was prodding and grasping at my cock with her nearly prehensile toes.

“I’ll have a patty...Yow! melt, please.”

“Are you all right, miss?”

“Yes yes Eek! I’m fine.”

We all looked up at him like the innocent schoolgirls we were.

With some regret, we dropped Cait off and went home. I needed to get changed back into boy clothes before the parents got home and found their son Chris turned into Chrissy.

After dinner, as I washed and Megan dried, she leaned towards me in a conspiratorial manner:

“Come to my room after this and I will help you with your anatomy homework.”

“Um, I’m not studying anatomy.”

“Tonight it’s your favorite subject, but you can make up another story for Mom and Dad. if you want.”

I arrived to find her wearing sweatpants and a sleeveless undershirt through which her dark nipples were visible and buzzing with nervous energy. I started to get aroused even before I learned what she had planned - it was bound to be something good. I didn’t have to wait for long, as she bounded over to her closet and fished out a box. She explained:

“You remember Scott, my old boyfriend, right?”

“You mean dorkboy? Yeah, I remember, I was beginning to wonder about your taste until you ditched him for Caitlin.”

“Well, he used to drop hints about wanting to try anal, a little at first and then kind of nagging, until finally I agreed. But it hurt, and worse, he got kind of aggressive ane, like he wanted it to hurt, and I made him stop. I decided anal wasn’t for me but I’ve heard other girls talk about it like it can be cool and liberating if you can find someone you really trust.”

She looked at me, blushing now in a really sexy way (is there a non-sexy way for a hot girl to blush?), and opened the box. There was a bottle of what must be lube, a sort of cone-shaped rubber thing with a disk and a ring on the back, and a dildo attachment that I guessed wasn’t for me.

“Is that thing what I think it is?”

“Yes, if you think it’s a butt-plug. We’re going to start with that, and if it goes well, we’ll move on to bigger objects. I figure I will never trust and love anyone more than I do you and Cait. Are you up for this project? Oh, I see you are.”

My pants by now were tenting noticeably, and I moved to take them off as Megan made sure her door was locked. On her way back to the bed she wriggled out of her sweatpants, revealing her long slender legs and smooth-shaven pussy. She positioned a couple of pillows under her belly and lay there with her lovely heart-shaped ass in the air, outlined by bikini-shaped tan lines left over from summer.

I knelt beside her and bent to kiss her smooth butt cheeks, running my hand up the inside of her thigh to her soft pussy lips.

“Oh that’s good little brother, but remember the task at hand!”

I picked up the lube and applied it to my fingers; when I began to massage the puckered entrance to her anus, she moaned softly. At first, her ring of muscle made it tight even for one finger, but I worked it in past one knuckle, then two, then tried a second finger as Megan continued to coo softly with each penetration. After a minute she seemed to relax more, and I lubed up the plug. When I had eased in part of the plug she said, “Ow ow! Wait,” and I stopped, just holding the protruding plug where it was. She reached down to stroke my cock with her elegant manicured fingers, grasping the shaft but only just grazing the sensitive underside of the glans. I was going to have to find some release pretty soon.

But now she decided she had had enough time to adjust, and I went back to work, pushing a little more of the plug into her ass with each motion, until the fattest part went in, as Megan moaned and sighed with evident satisfaction.

“Omigod, Megan, that looks so hot, the little round base poking out of your tight ass with its ring, like your butt has a handle.”

“You are such a little freak, Chris! Now, on your back!”

I naturally obeyed my big sister, and she knelt on either side of my head and lowered her twat onto my face. I loved the feel of her baby-smooth pubis against my nose and cheeks as I kissed her labia and began to lick at her vagina, flicking my tongue now and then up to her clit.

“Oh, you are such an obedient little boy,” she said, “but now I need you inside me.” And she slid slowly down my body, letting me kiss first her flat belly and then her petite perky tits. I took a nipple into my mouth and suckled, pressing the firm point between my tongue and palate. Finally, she lowered her now-wet pussy onto my waiting cock, guiding the head in with her hand and grunting, “unk! Oh yeah, fuck your horny sister!”

I reached down and cupped her butt cheeks in my greedy hands, holding her as I thrust upward, deeper and deeper into her hot flesh. When we had fallen into a rhythm I reached farther and grabbed the ring of the butt-plug; I worked it out and in again in time with my thrusting cock. This drove her wild, and I looked up to see her delicate features transformed by desire, her lips in a little O, her cheeks flushed, and her brows furrowed in concentration. Her grunts became ever louder:

“Unk ooh GURG GURG! Fuck me, little brother, stick it in my tiny ass! Shove it in me!”

“Ssh, Megan, they’ll hear us!”

I pulled her head down and covered her mouth with mine, feeling her panting breath and muffled moans of pleasure, which became longer and lower as she went from frenzy to climax. I grabbed the plug again and pushed down, and the thought of fucking her in both holes drove me to my own shuddering orgasm. I filled my sister’s welcoming insides with my seed and collapsed onto my back.

She lay on top of me, pressing down with the sweet hot weight of her whole slender body as my prick gradually softened inside her, her long black hair making a curtain around our heads. I could have lain there all night, I think, but there was a knock at the door.

“Come on, kids,” Mom shouted through the door, “you know it’s not good to stay up studying too late!”

I gave Megan a last kiss and told her she was the sluttiest, most wonderful big sister a boy or a girl could have, and slunk off to my own room with my head full of plans for her sweet ass.