You screwed up.

You screwed around with the Womping Willow and hurt your leg really bad.. since Madam Pomfrey wasn't in at this hour since its passed curfew.. you had to go to your potions professor.. praying he wouldn't lecture you too hard.

You did.

He sat you on one of the work tables and made up a healing potion and salve.. all the whilst lecturing you over and over again especially since you're a Slytherin..

so he stood between your legs.. you decided to ignore that..

and he applied the healing salve.

"How could you be so stupid?" he chastised.