Make her earn it [Ass2Mouth]

While it's tempting to get blowjobs from Sarah for hours, you have a limited amount of sexual endurance and you're confident there's more wonders to be experienced and enjoyed throughout the day. Still, there's some be fun to be had in returning it to her.

"I'm keeping it." You say with a naughty grin, holding it above her head. "Unless... you lube it back up with your mouth."

"But... I can't do that! It's just been in my butt!" She protests.

"Fine, have it your way. You'll be drinking nothing but my cum all day. In front of everyone. Including at lunchtime, in the dining hall."

She screws her nose up, but you've successfully made your point.

"Fine... I'll do it. Give it here."

But you're not sure of the rules - perhaps as soon as she takes it off you, you'll lose power over her.

"Lick it clean while I hold it." You stand up and hold it at head height, so she has to come out from under your desk and stand up in front of the whole class as she degrades herself.

"Slowly." You say with an air of dominance.

Sarah keeps her nose and eyes scrunched as she hesitantly licks the plug clean.

"What does it taste like?" You demand.

"Ass." Sarah admits, in a complaining tone.

"Disgusting!" Tom mutters. Sarah turns an even brighter shade of red.

"Put the whole thing in your mouth now." You instruct.

Sarah complies, opening up and taking the entire toy inside.

"Suck it like it's a cock." You don't know where this sadistic streak has come from, but you're enjoying yourself too much to stop now.

Sarah bobs her head back and forth until whatever ass juices and lube were coating the plug before has been entirely replaced by her saliva. When you're satisfied, you pull the toy away.

"Swallow." You say, danging her butt plug out of her reach.

"Mmmmm!" Sarah replies desperately, the mix of spit and juices in her mouth something she really doesn't want to have to ingest.

"Swallow or I keep it." You don't budge.

Sarah gulps it down, retching a bit afterwards.

"Gross!" Tom says with unconcealed disgust.

You go for more.

"Bend over and spread your cheeks for the class. I'll put it back in myself."

"John, please!" Sarah squeaks. "That wasn't part of the deal!"

"I have altered the deal. Pray I don't alter it any further."

I've always wanted an excuse to say that.

Sarah whimpers as she bends over, exposing her butt to the class. She spreads her buttcheeks, and now everyone including you can see her cute pussy and asshole.

"Bend over further." You demand. "Push your forehead against the floor, but don't bend your knees."

With a little difficulty, she complies, and then returns her hands to her asscheeks. Now she truly is as face-down, ass-up as possible. She has been completely and utterly humiliated in front of her peers.

"Tell me you're sorry for being such a dumb slut, and you promise to work harder to keep your butt plug in its rightful place."

"I'm sorry for being such a dumb slut, and I promise to work harder to keep my butt plug in its rightful place!" She says in a loud but wobbly voice.

"Now beg me to put it inside you, using the most dirty words you can think of. Convince me you deserve it."

There's a pause before Sarah speaks.

"Please... err... please shove my nasty... perverted... fetish toy into my greedy tight... fuckhole! I'm a naughty nympho butt slut and my asshole should be kept stuffed full at all times!"

You're genuinely impressed that such a mousey little girl could come up with such lewd dirty talk.

"Good girl."

You slam the plug into her waiting ass with one strong push, almost making her fall over with surprise, and eliciting a nice pained squeak from her. Looking around at the class proudly, you see a myriad of expressions. Some are in awe, others horrified.

Uh-oh, this has awakened something in me, hasn't it. Did I take it too far?

Someone is clapping behind you. You turn around to see Mrs. Fletcher smiling an evil content smile as she applauds your efforts. "Bravo, Mr. Doe. Excellent job teaching Sarah her lesson. You other boys should try to learn from his example."