I was trapped under the ninja’s ass, so close to my sister. I tried wiggling myself out but Nina seemed to have felt something and would clench her ass cheeks on me. She had very strong butt muscles because it felt like the life was being squeezed out of me. The soft fatty tissue turned into buns of steel. It was kind of sexy being smothered by this girl’s ass, but also kind of painful. Nina then stood up and pulled up her bottoms before I could escape. 

“I’m now stuck with a new girl instead of my sister or Steph. And Katie is going to kill me if I ever see her again. Shit.” I said to myself. 

I felt some vibrations and a quick puff of gas poofed out Nina’s anus. It may have been small and silent, but man was it deadly. This fart instantly made me gag and want to throw up. I scrambled to get away for some fresh air but she just clenched her cheeks together again and held me in place. Not only could I not breathe but her muscles were making me feel like I was going to pop. Luckily the smell didn’t last long as she walked out of the change room ready for gym class. All the students talked about random stuff as they began jogging and stretching. As long as I didn’t move, her cheeks remained soft and squishy. Feeling her soft skin rubbing against my naked body was starting to turn me on. My mind immediately focused on her anus as I watched it move around. When Nina sat down to stretch more, the weight and pressure pushed me up against her hole. My dick slide in between her tight hole and it felt amazing. She moaned internally and tightened her body. I could feel pressure from every side of me but it sort of hurt in a good way. 

“Hey Nina, you have a fourth period spare right? Wanna hangout at my place?” Steph asked smacking her butt then continuing, “Damn nice ass girl, you’ve been doing squats.” 

I was hit with the shock wave as everything vibrated and jiggled. I thrusted deeper and I couldn’t hold it in any longer. I tensed my body and shot my load into Nina’s ass hole. She couldn’t explain why but she got very horny from all of my tiny movements. She smacked Steph’s butt in return but then lingered her hand on it. Her body froze not knowing what to do next. Both of them were pumped full of hormones from Katie and myself. Nina however, was still a virgin and never came out that she was lesbian. In this moment, her brain wouldn’t let her speak. Steph had to make the next move for her.

“Well I’ll see you at my place after third period.” Steph said winking and heading back to start fitness class.

Nina was left awestruck but had a good guess that Steph wanted something more than just hanging out. She smiled and then joined the class as well. I heard their conversation and decided to stay with Nina so I could get back to Katie. The teacher ended up being lazy and decided on the class to play dodgeball instead. From listening and feeling Nina’s movements, I was shocked at how good she was. She was so fast with dodging and even throwing. Her small size probably helped too, but I don’t think she was hit once. Only proving my theory that she really is a ninja. The games were pretty rough on me. All the quick movements and tight butt clenching were exhausting. I had to fight back against her cheeks from squeezing and popping me. Plus to make everything worse, she let some more tiny silent farts out. I was being suffocated and tormented by this girl’s ass. By the time class was over, I had more of a workout than all the girls.

“Class is over, time to hit the shower girls.” The teacher instructed. 

Shit, the shower. If I don’t do something then I will surely get washed down the drain. I decided entering this girl’s butt was my best option. I tried to stick my hand inside but every movement I made just caused her ass to get tighter. I could feel her getting undressed and I tried to leave to jump into her panties but I couldn’t. She was gripping me in there. She joined the other girl’s in the shower and water started running down into her crack. I pushed my hand hard and deep into her tight hole, praying that I will survive the wash. Nina quivered in response and then started with washing her ass with the bar of soap. Déjà vu cursed through my mind as I got stuck to the bar. She then rubbed me face first across her wet skin, dragging my naked body against hers. I was painfully grinded into her smelly pits and vagina while taking in mouthfuls of soap. I was then rubbed up against her belly and along her small boobs which actually felt nice. 

“Hey Nina, I forgot soap, can I use yours?” A classmate spoke up.

“Yeah me too.” Every other classmate added.

I just thought to myself, how in the flying fuck does every single girl in this class forget soap? It’s like someone is dictating my life and making this impossible moment happen just for entertainment purposes. 

“Sure, here you go.” Nina passed the soap off.

I was then passed around and rubbed into each girl’s rank smelly pits. One after the next the used me to wash their sweaty bodies and clean their butt holes. I couldn’t open my eyes while I died underneath all the soap but I could imagine the glorious experience it would be if it wasn’t torturous. From the feeling on my body, I could tell some girls were skinny and fit, while others were fat and squishy. Some girls even had pubic hair that scratched my face profusely. Even through all the nasty different scents and vicious scrubbing, I still got turned on by thought of it. I’m not sure which girl, but one of them even has my cum rubbed into them. Unfortunately the fat girls felt softer, so they won the prize. I hope it wasn’t fat Carol though. 

“Thanks Nina.” The last girl said returning the soap.

Nina smiled and then did one last final scrub to her ass to make sure it was clean. This time I knew it was safe to jump back off and I did so at the perfect time. I managed to use the pressure and soapy lube to shoot myself through her tight anus and into her bowels. Her ass clenched back up after my entrance and trapped me inside. There wasn’t much I could do until fourth period so I laid back into a groove and waited. Eventually, the time came where Nina and Steph met up. They took Nina’s car back to Steph’s place and went up to her room.

“I got this new lipstick, its strawberry flavoured.” Steph said going through her drawers and then putting it on. 

“Oh cool, could I try it?” Nina replied.

“Yeah but to really taste it you have to kiss. I don’t mind if you kiss me.” Steph said moving closer to Nina.

“Oh okay then.” Nina shyly giggled and then locked lips with Steph. 

Both girls lingered the kiss and I knew this is where I had to jump in. I massaged the inside of her bowels until she accidentally slipped out a moan while kissing Steph.