Severus Snape was always a bitter man, always with the dour look on his face. He also seemed to be permanently stressed, and Harry believed that was probably the better half of the man's problem.

That was the reason for Harry's current predicament.

Harry was sitting beneath Snape's desk, his invisibility cloak hiding him from sight. A note in his palm to give to the man if he needed to ensure the man's silence.

See he'd been so sure that the man's problem was stress that he had accepted Ron's challenge to prove it. Only when Hermione asked how exactly he would do that, that he realized he'd have to do something pretty drastic, if he were to infact prove that the man's problem was stress, he'd have to find a way to make the man release the pent up stress. He only knew one way to release a large amount of stress at once. And that was immense pleasure.

So Harry waited until the man finished giving the instructions for the seventh year class he had now. Once the man sat down and had been down for a few minutes, Harry placed the note on Severus's lap. The man looked down and saw nothing but the note. He opened it and found the messily scrawled message

'If you make any indication of knowledge that I'm here, you'll have to either admit that you let your guard down enough to not notice someone was under your desk, or explain why you allowed a student to be between your legs, especially in school hours.'

Severus was fuming. It took real cunning to get a man like him into this sort of situation, Slytherin cunning. He knew it also took a large amount of bravery, or stupidity to put a man like him into this sort of situation, a Gryffindor trait. So either the Snakes and the Lions were working together (Which indicated that Hell had frozen over) or there was a very clever Gryffindor who wasn't afraid to get kicked out of school. The only particularly clever Gryffindor he knew of was Miss Granger, but she would never condone, much less pull off something such as this, her morality simply wouldn't allow it.

So Severus sat and watched his class, doing his best to keep silent, which was a little difficult, considering the student had their hand in his pants, and was removing his member from his trousers.

Severus inhaled sharply as his cock was taken into their mouth. He went from flaccid to rock hard in a matter of seconds. He silently cast a glamour and a silencing spell over the entire area of his desk. The students saw him silently watching them with a stern eye, whilst he was in fact, trying very hard to control his breathing. Whoever it was under his desk, was either very well trained, or a natural at blowjobs, because he wasn't far off biting his hand to stay quiet.

After a few moments, Severus groaned and bit his hand. His eyes closed and he tried to hold back his moans, only to instead release desperate little gasps and whimpers of pleasure. He looked up, his students were none the wiser, so he swallowed his pride and moved his hand down from his mouth into the students hair. His breathing harsh and irregular he thrust into their mouth a little. At hearing a soft gag he almost felt guilty, but then the student swallowed him down, and he gave a deep gutteral groan in response.

He tightened his grip in their hair and began snapping his hips forward continuously. As the student orally pleasured him, their fingers moved up to deftly fondle his sac. He moaned out throatily and cursed under his rapid and irregular breath. He felt the tightness building up in his lower abdomen.

Severus jerked the students hair hard once as their only warning before he spilled his seed down their throat. Once he'd finished, they pulled away gasping for breath, before going back and making sure they milked every last drop from him.

The student made no further movement, and so once he had his breathing and appearance back to the norm, he dropped the glamour and the silencing spell. He dismissed the class once everyone was done and locked the door before moving away from his desk to see who it was who decided to blow him in the middle of class.

Harry grinned sheepishly up at the man as his shock registered on his face.

"Am I not who you were expecting Sir?" Harry managed to look completely innocent. Severus was flabaghasted. "I don't know who I was expecting, but it was most cirtainly not you."

Harry chuckled, "You're always so uptight, so stressed, I'd simply love to help you let out all your stress.

Severus deadpanned. "You have no idea what you just got yourself into brat."

There you go. I was going to make this a one-shot, but I decided it needs to become dark and evil and need to be XXX rated. Cause honestly, half the time R doesn't cover the shit that I write.