He hadn't meant to see it. He didn't think anyone would be in the common room at all at this hour, as a matter of fact. A nightmare had woke him and he crept silently down the stairs wanting to just sit and think by the fire, but he stopped short when he saw i her /i in her glow of the flames.
She was lying reclined on the sofa but he could see that her shirt was open and that her hand was moving between her legs. Her face, breasts, and the leg that draped over the top of the sofa looked gold in the firelight. Her hair, which hung over the arm of the sofa, gleamed brightly. He thought that not even Aphrodite herself could be more beautiful. His jaw dropped and his pajama bottoms tightened as he watched her hand come up to tug at a nipple, the thought of leaving not even in his thoughts anymore. He watched her lips part slightly and could tell she was whispering something, but couldn't tell what.
He stayed in the shadow of the stairwell and watched her, his hand unconsciously moving over his erection. His knees felt weak as her moans started getting louder and he jumped back in fright, thinking she caught him watching, when his name fell from her lips. When her moans continued he peeked back out cautiously, barely able to suppress his own moan when he realized that Hermione Granger was masturbating while thinking of him.
He continued to watch her, getting more and more turned on as her orgasm approached. Her chest heaved, the hand between her legs moved faster, and the hand playing with her breasts got rougher as she cried his name a little louder.
"Neville!" she gasped out finally, arching into her hand.
"Neville!" she cried again, and he felt a hand on his shoulder. He looked up, blinking and saw Seamus standing over him, shoving him roughly on his arm. "Quit wanking and get out of bed, you prat. We've class in 45 minutes. I've been trying to get you up for 10 minutes now."
Neville sighed, blushing, and got of bed, hurrying to the shower. Standing under the cold spray he muttered to himself, "I've got to do something soon, this is the third time this week I've been caught dreaming about her."