The cauldron simmered below her. She reached over and grabbed her vial. This was always the tricky part. The worst part of potions class was trying to get the potion into the vial, which either involved dipping it in and trying not to get it on your hands or using a ladle (which she didn't have).
"Miss Lovegood, may I ask what is taking you so long?" Snape glared at her. "The rest of the class has left."
"Oh um, sorry professor. It's just hard to get it in the vial." Luna said innocently.
Snape sneered. "This isn't a harmful potion, so as long as you got it right then it shouldn't be a problem dipping your hand in."
Luna looked back down at her potion. She slowly dipped the vial into the cauldron, accidentally getting some on her hand.
She pulled her hand back out and put the stopper in.
Snape realized what was going on as soon as it happened.
"Miss Lovegood.. you might want to sit down.." Snape said.
Luna was starting to feel dizzy. "P-professor I think I did it wrong.."
Snape was at her side almost holding her up.
"Did you dip your hand in it?" He asked quickly.
"I.. I think so."
Her chest was growing and her ass thickening.
"Miss Lovegood, did you put any mint in your potion?" Snape waited for her answer. If she had then it would come out as a perfect pepperup potion. If she didn't- well…
Luna shook her head no.
"Oh no.." The potion she just dipped her hand into was to turn her into what muggles call "bimbo". The side effects would make her and the people around her horny, and he couldn't have that.
Could he? Maybe just a little bit of sex couldn't hurt.
Luna snapped into some sort of trance. The buttons on her shirt popped off, and her skirt raised slightly over her growing ass.
Snape walked backward.
Luna looked at the potions master. Her white bra now exposed along with her matching knickers.
She stood up and walked to her now still potions master.
"Professor, do I make you horny?" Luna asked seductively. She pressed her chest against his.
Snape backed into a wall. Why was he backing up? This was a perfect chance to finally relieve himself of a lot of stress! Why turn it down?
Luna followed him back. She nudged her thigh against his steadily hardening cock.
He leaned his head back and closed his eyes. He was not going to get fired because of this.
Their lips nearly touched. Something snapped in Snape's mind.
He closed the gap between them and instantly started grabbing at her ass. Luna moaned into his mouth.
Snape pushed her into a desk and lifted her on it. She spread her legs and pushed aside her panties, playing with her clit.
He unzipped his pants and slipped them down just enough to where he could access his cock. He pressed the head to her opening. She was literally dripping wet.
He pushed the whole thing in all in one go. Oh how it felt good.
Snape could feel the pent up nerves leaving him as he pushed in and out. Luna made every noise she could to make him go faster.
Faster and faster he went. Luna clenched around his cock and grabbed at his shoulders, pulling them closer.
Luna squealed with delight as she came around him. Snape made sure her high was as good as it could be.
He went to pull out but instead rammed back in with all his might. He hadn't even realized he was close until he came deep inside her.
This time he pulled out for real. Luna leaned her head back. The potion was wearing off.
"Oh professor… that was amazing."
Snape opened his mouth to respond when the door creaked slightly. He didn't recall leaving it open.
Both of them looked at the door to see an eye through the crack.
"Who's there? Snape said while zipping up his pants. He handed Luna his wand to fix her blouse and walked over to the door.
He snatched the door open to see none other than Hermione Granger.
"Why are you here?" Snape asked.
"I- I was looking for Luna.. but it seems she's busy." Said Hermione smiling.
Snape turned a little red. "How much of that did you see?"
"All of it."