A, of course

"Well, my dad said he'd get me something cool if I got an A," Melissa said, blushing. "What do I have to do to get an A?"

Matt opened his mouth to answer, any answer, when Mr. Atlas' memory kicked in, giving the answer he had apparently given multiple times since getting the teaching position - no A without the a. He remembered watching the cheerleaders as they pranced on the field, their movements drawing everyone's eyes either to their bouncing breasts or firm asses, and realized this was an opportunity that he couldn't pass up. "Right over here," he said, guiding her to stand in front of the teacher's desk, accessing the memories that the action called up.

He turned Melissa to face the desk, his hands on her arms. "Bend over," he instructed, sliding his hands down to grasp her wrists, moving her hands to the surface of the desk. The movement stretched him over her back, Matt's hard cock pressing against her supple ass. He pressed harder, pushing Melissa's thighs against the edge of the desk. "I think you know what it will take for an A."

"You seem excited today," she purred, pressing her ass back, "but I can't risk it today. I'm right in the middle of my cycle, and I could get pregnant."

"If you wanted a B, that could be a problem. Lucky for you, you asked for an A." Matt slid his hand off her arm, still pinning her to the desk as he reached for the bottom drawer, pulling out a large bottle of lotion.

"You... you mean... but I've never done that before."

"Don't worry, I'll be gentle." Matt ran his hands up and down her arms, transitioning naturally from her arms to her sides, sliding forward to cup over her large breasts, kneading them gently, pushing against her softness rhythmically.

"O... Okay," Melissa whispered, resigned, and Matt slid his hands down her sides, hooking his fingers into the waistband of her cheer skirt, pulling them down and exposing her ass.

"Very nice," he murmured, hands stroking her ass. His cock was throbbing in his pants in anticipation, and for a moment he forgot it wasn't really his cock he felt throbbing. That moment ended when his hand left her ass to unzip the front of his pants. The fabric peeled apart and dropped from his hips, exposing a cock that was both thinner and shorter than the one he had been used to. Matt smirked at the sight, then reached for the lotion. He squirted a generous portion onto his hand, swirling it around the shaft, then squeezing more directly onto Melissa's asshole. She gasped as the cold lotion hit her skid, and again when Matt's finger spread it around her sphincter, then pushing some inside her. He grabbed his slick cock and pressed the greased up tip against her. "Take a deep breath and relax," he advised, and pressed forward.

Matt's left hand went to Melissa's hip while his right guided his cock, pressing slowly until the tip popped past her sphincter. The girl let out a pained moan, and Matt could tell the only reason the moan wasn't a scream was the fact she was biting her lower lip. His suspicions were confirmed when she turned to look over her shoulder at the person she saw as her math teacher.

He pressed harder, watching as his cock sank into Melissa's ass inch by inch, the erotic sight almost drowned out by the sensation itself. When his cock was halfway inside her, Matt moved his hand to her waist, gripping her hips tightly and pushing his hips until they rested on the smooth slopes of her ass. "Are you okay?" he asked, not moving hips or hands. Mutely Melissa nodded, and Matt began to move his hips, watching as his cock slid in and out of her tight, teenage ass. Every moment made her clench, making him feel as if she were trying to pull his cock out by the root.

As he fucked her, his hands slid up her sides, underneath the tight shirt until his hands cupped Melissa's firm breasts. They jiggled with each thrust, the girl's gasps now coming in panting grunts as Matt's thrusts got both harder and faster. Then he lost all control, thrusting as deep as he could as he felt his orgasm wash over him. He held his cock as deep inside the cheerleader as he could get, his cock throbbing with each spurt of cum he shot deep inside her.

"Oh, god," he moaned, his hands squeezing her breasts, his weight fully on her back as Melissa seemed to sigh in relief.

"Did... did I earn my A?" she asked in a trembling voice.

"Yeah, you did," he said even though Matt didn't have any way to tell for certain, or even if Mr. Atlas would remember fully what happened, but he promised himself to check later. Then it hit him - if he jumped back into his body, there would be no way the teacher could miss this, with his cock still deep inside the eighteen year old ass. He jumped back into his body, which was in the final few minutes of a chemistry lecture. He found he could remember every moment of the lecture, with a recollection even better than if he had been here, along with a complete recollection of fucking Melissa's tight ass. Matt's cock, his own this time, twitched in his pants at the memories, and he wondered what other mischief he might get into with this strange new ability.