Ms. Nanci gives in

"OK, fine!" Ms. Nanci interrupts, grabbing your hips to keep you from letting the last bit of her cock out of your butt.

"Well?" You smirk, looking back at her expectantly.

Sighing, she starts: "Please, Doug, fuck me with that sexy little behind of yours. I beg you, squeeze down on my cock and gyrate your hips. I- I really need to cum!"

You stay silent, waiting for her to remember that she left out an important part.

"Argh! Yes, I promise I will fix your grades, just fuck me already!"

There it is! You got her! Smiling, you stop trying to pull away, and let half of her cock back in, incredibly relieved that you don't have to resist your own urges any longer.

You both let out a moan of pleasure as you squeeze down with all your might, sway your hips from side to side, lean back into her so her cock penetrates the deepest parts of your butt, and even turn your head to give her a wet, sloppy kiss. Ms. Nanci doesn't thrust back into you, instead letting you do all the work. You don't mind, having never felt this sexy ever before.

The smell and sounds of sex fill the room as you and the woman you've beaten at her own game are lost in a trance of raw animal lust, unable to think of anything but fucking.

Since your teacher was already on the edge, it takes only a minute until she loses control, grabs your hips and slams into you, releasing an entire load deep into your bowels. The warm, gushing fluid makes your stomach bulge a bit, fills you with a strange sense of pride and pushes your own orgasm even closer. Part of you wants to ask Ms. Nanci to give you a reach-around, but you decide against it to avoid the risk of changing her mind on who's the boss.

Once she is sure her cock's last spurts are over, Ms. Nanci pulls her cock out of your butt, immensely satisfied and even a little exhausted. As its head comes out (with a loud 'plop!'), you finally let go, and a stream of cum gushes from your own, smaller cock in a straight line over the desk and landing on the chalk board.

Weak in the knees, you turn around and fall into your teacher's arms. She gives you another kiss.