On the whiteboard

As Lisa began to write the first math problem, she felt the heat of Alissa's body approaching from behind. Without a word, Alissa pressed against her, the hardness of her dick nudging between Lisa's thighs. Lisa's breath hitched as Alissa found her entrance and slid inside with a single, fluid thrust. The sensation of fullness made Lisa's knees weak, but she steadied herself against the whiteboard, determined to maintain some semblance of control.

Alissa began to move, her hips snapping forward with an urgency that belied her casual demeanor. Lisa bit her lip to stifle a moan, the chalk still clutched in her hand as she finished writing the problem. She turned her head slightly, her eyes locking with Alissa's, a silent challenge passing between them.

"Solve it," Lisa said, her voice barely above a whisper. She could feel Alissa's dick twitch inside her, a testament to the futanari's arousal at the game they were playing.

Alissa reached around Lisa, her hand brushing against the tutor's bare stomach as she took the chalk. With her cock still buried deep inside Lisa, she began to scrawl the solution on the board, her movements jerky with the effort of both fucking and focusing on the math.

The correct answer elicited a reward from Lisa, who pushed back against Alissa, encouraging her to increase her pace. Alissa complied, her thrusts growing faster, more insistent. Lisa's grip on the whiteboard tightened, her knuckles turning white as she fought to keep her composure.

"Next problem," Lisa managed to say, erasing the solved equation with a trembling hand. She wrote down another, her body rocking with each of Alissa's thrusts. This time, when she turned to offer the pen to Alissa, she found the futanari's eyes glazed over with lust, her attention solely on the rhythm of their bodies.

With a smirk, Lisa stepped forward, Alissa's dick slipping out of her with a wet sound that echoed in the empty room. Alissa let out a whine of protest, but Lisa silenced her with a look.

"Math first, Alissa," she chided gently, her hand reaching back to stroke Alissa's length teasingly. "Then pleasure."

Reluctantly, Alissa took the pen and set to work on the second problem. Lisa watched her, a mixture of pride and desire swelling within her. Alissa was brilliant, there was no denying that, but her true potential was unlocked when her body was as engaged as her mind.

As Alissa solved the second problem, Lisa resumed her position at the whiteboard, her ass thrust out in invitation. Alissa didn't need further encouragement. She was inside Lisa once more, their bodies squishing together.

They continued this way, a symphony of moans and gasps punctuating the quiet room as they worked through the problems. By the time they reached the sixth equation, Lisa was a quivering mess of need. Her pussy clenched around Alissa's dick, her orgasm building with each passing moment.

"I can't wait," Lisa breathed out, her forehead resting against the cool whiteboard. "Fuck me on the couch."