He scowled at Lily’s essay, marking a bold D in red. She leaned in to his ear, her lips as crimson as the ink. "That's not the D you wanted to give me is it sir?"

She dropped to her knees, unzipping his trousers. Her tongue teased him eagerly, the red lipstick marking him in return. Starting slow and building up speed.

“Lily! Oh, fuck!” His body shuddered, muscles locking, hips jerking as he emptied himself into her eager mouth.

She swallowed, licking her red lips. “Guess I aced the oral exam.”

He smirked, breathless. “And now for extra credit.”