"In here," Maya commanded.
Leading me by the wrist, my sister pulled me into... the women's bathroom, located right next to the women's locker room. I held my breath but fortunately, it was empty.
The lack of urinals was the biggest thing that differentiated it from the one I normally use. That and it smelled better. A lot better. I didn't have a lot of time to take it in before Maya pulled me into the last stall and pushed me down on the closed toilet seat.
We were both still sweaty from practice and I was incredibly horny from staring at her barely dressed body for nearly an hour. Judging by the dark spot in her running shorts that was more than just sweat, she was, too.
Only bothering to push down our pants as much as physically necessary, Maya straddled me. The moment my cock slid in her, she closed her eyes and let out a sigh. I coated my middle finger in my mouth and reached around her to worm it inside her ass, just the way she liked it.
"I wish you had two dicks," Maya laughed.
"Me, too."
"If I cum before you do, you're finishing in my ass."
"Deal," I said, reaching up to play with her nipples.
The door to the bathroom opened and I froze. Maya continued, unperturbed. I wondered if there was any situation that she couldn't master. After everything I tried, I wasn't sure.
"Maya? You in here?" Sam called out.
Sam was also on the track team, joining the same year Maya did. They weren't friends as far as I was aware but they were on friendly terms. Before Maya, Sam had been an occasional visitor in one of my fantasies.
Not that I wanted anyone to catch me fucking my sister but if I had a choice, it definitely wouldn't be Sam.
"Yeah," Maya called out.
"You busy? I can come back later."
"No, what's up?"
Not busy? I raised an eyebrow at her but she just grinned at me. Footsteps came closer and Maya rode me harder. Her fingers dug into my shoulders.
"It's actually about your brother," Sam said.
The voice was really close. Through the bottom gap of the door, I saw the soles of Sam's running shoes. She was right on the other side. I held my breath.
"What do you want with Buttface?" Maya asked, sticking out her tongue at me.
"Do you know if he has a girlfriend?"
Both of us raised our eyebrows at that. Did I have a girlfriend? Was Maya my girlfriend?
Silently, I mouthed "you" at Maya. She shook her head.
"No, he doesn't. To be honest, I don't think he's ever had a girlfriend before," Maya lied.
"Oh," Sam squeaked. "Does he, uh, have a boyfriend?"
Maya giggled. I frantically shook my head but Maya just grinned. I squeezed her nipple until she winced and her eyes watered.
"No," Maya said in a high-pitched squeal and I let go. "He's not gay. As far as I know. Why?"
"I wanted to know if you'd be okay with me asking him out for coffee sometime."
"Really? Him?" Maya guffawed.
"I think he's kinda cute."
Sam thought I was cute? That was a surprise. Though it was hard to think about the possibility of dating Sam with Maya squeezing my dick.
"Well..." Maya said and hesitated, rolling her eyes at me, "okay."
"Really?" Sam said, sounding surprised.
"Yeah. Why not? It's about time my baby brother lost his virginity," Maya laughed loudly.
"Do you always have to be so..." Sam groaned from the other side but thought better of finishing that sentence. "Thanks!"
And then we were alone again. Maya still occasionally giggled, muttering "virgin" under her breath. She was moving slower but in no way less stimulating.
"I'd rather date you," I said, waiting long enough to make sure Sam was out of earshot.
"That's because you're an idiot," Maya said, pinching me in the side. "You still haven't gotten it, have you? We can never date. Ever."
"Sure but I'm not gonna date someone else while we're... you know," I said, thrusting my hip.
"Is it because you're not man enough to handle two women?" Maya teased.
"Are you saying you want me to date Sam?"
"I don't care what you do," Maya snapped at me. "I am unflappable."
The door opened and both of us went quiet. Maya did not stop riding me, however. It seemed to be just one person using the faucet, until we suddenly heard a high-pitched squeal of disgust.
"Ewwwww."
"What?" another person asked. It was Sonya.
"Check out what Craig just sent me," the squealer said. It was Greta.
"Eww," Sonya said but after a short pause continued, "is it really that big?"
"Yeah," Greta said.
"You've seen it?"
"I made the mistake of hooking up with him last spring break. He's been sending me dick pics ever since."
"And you don't want that beauty?"
"Ugh, I forgot how much of a size queen you are. Fucking slut."
"I haven't gotten laid all week, I'm not a slut!"
Grinning, Maya leaned in close.
"I've seen Craig's dick. Yours is bigger," Maya whispered. "And I changed my mind. Cum in my pussy with your big cock."
It didn't take me long after that to finish inside her, listening to Greta and Sonya chatter about their sex lives.
***
As nice as Sam was, I couldn't stop thinking about my sister. All evening long, I had been picturing the look on Maya's face when I showed up arm in arm with Sam. It wasn't fair to my date, I knew that, but it was what my sister wanted.
At least that's how I had interpreted her hints. She wanted me to humiliate her and what was more humiliating than spending a romantic evening with another woman?
Dinner had been nice and we mostly talked about running. I have known Sam for over a year, so we didn't have to do a lot of chit-chatting. She was an only child and a year older than Maya, though she repeated several times she didn't think of me at all like a "baby brother."
All in all, it was going well. I just wish I could have enjoyed it the way I would have just a month prior.
When we drove up to the house, the light upstairs in Maya's room was off. Sam parked the car on the curb and I used the opportunity to take another look at Maya's room. Ever so slightly, the curtain moved and I knew she was watching.
"Nice house," Sam commented.
"Yup. Lived there my entire life."
"Reminds me of back home."
I unlocked the door and entered, hoping the coast was clear. The sound of a movie came from the living room, which was a good sign.
"Let's go straight upstairs unless you really want to meet my parents."
Sam giggled and slipped out of her shoes. Upstairs, I snuck a glance at Maya's room but the door was firmly shut. Light penetrated through the gap on the bottom, so she was definitely home.
"Way bigger than my dorm room," Sam remarked upon entering my bedroom.
