Humiliated Until Cumming

I was fourteen, and my mistress was a girl from school called Chloe. Most of our friends are on the same bus as us, and they all know of our relationship and my gender issues. Occasionally, they join in on our scenes. One day on the way home from school, my mistress decided to make me suffer. Once everyone who didn't know about us got off the bus, she made me switch to sitting in the back row and take off all of my clothes. Then, she tied my hands to the seat and my legs to the seat legs using some scarves she had, as it was February and freezing. She called our friends to the back rows. The bus driver couldn't see us - the bus is layed out oddly so I was hidden from sight. She and our friends worked me up, pinching my tits, fingering my pussy and ass, calling me a whore. Dirty talk and exhibisionism was always one of my turn ons, so before long, I was aching to come. But my mistress had other ideas. I was the last person to get off the bus, so she said that I should get to cum last. By that stage, only three people aside from us were on the bus - two girls and one boy. They each got to do whatever they wanted to me until they came. The boy Padraic made me give him a blow job. He pulled my hair, pushing his cock deep into my mouth and throat-fucking me until he was about to cum. Then he pulled out and began jerking off right in front of my face. "You're such a dirty fucking whore, Elliot. I bet you'd love to taste my cum. Yeah? Of course you would. You'd swallow every drop of it and beg for more, you filthy slut. Beg for it." He kept going until I was begging for him to cum over me. When I did, he came all over my face and boobs. One of the girls, Nora, was next. She got the vibrator out of my mistress's bag, slid it into my pussy, and turned it on as high as it would go. She made me suck her tits as she thrust the dildo in and out of me as fast as she could, daring me to cum before she did. Thankfully, I managed to hold out and she took out the vibrator and shoved it into herself. She untied my hands enough for me to bend down and suck at her clit until she came. Finally, Aisling - a trans girl. She made me suck on her cock, but not as much as Padraic did. She fingered my ass as I sucked her off. "Such a filthy whore. You like that don't you? Yeah. I bet you'd love to have my cock in your soaking pussy, but whores like you don't get it like that." Then she thrust into my ass. It burned because of the lack of lube, but I loved it, and the pain faded after a minute. She came in my ass, then pulled out and stroked herself until she came again all over my face, chest, and pussy. Then, without giving me a moment to rest, my mistress began fisting me. "Such a good little slave, making everyone cum like the whore you are. Do you want to cum?" By that stage, I was so wet that she could fit her entire fist and wrist into my pussy. "You do? Go on then, squirt like a fucking whore." That did it. I squirted all over her hand and the floor of the bus. She untied me and shoved the vibrator into me. "Good whore. But you got the floor messy, and you're covered in cum. Clean it up." She made me lick the cum off the floor while Aisling and Padraic jacked off over me again. When I was finished, Padraic began fucking me in the ass and Aisling shoved her cock between my boobs and used them like a pussy. Nora just fingered herself as she watched, making me lick her ass when she was close. They all came over me, and my mistress made me wipe their cum up with my hands and eat it all. By that stage, I had cum several times from being fucked, and from the vibrator, but my mistress didn't let me get dressed yet. "You're going to cum one more time, just to prove what a slut you are," she said once Aisling, Nora and Padraic dressed and got off at their stop. "Before you even get home." She made me get dressed with the vibrator still in me and tied me up again, watching me suffer and cum, trying not to moan. By the time I reached my stop, I had cum two or three times in my pants, and my skirt was soaked. She made me leave the bus like that and told me to leave the vibrator in until morning. It was a remote control one, so she turned it off for a while, but at random moments when I was doing homework, she'd turn it on, and I woke up because of it several times during the night when she'd turn it on and leave it on until I had squirted at least once.