I knock softly on the door to Snape's office, the bag in my hand clinking with many empty bottles. The ones that are still full of Wolfsbane Potion are hidden away in my trunk, protected by a spell.
"Enter," Snape says.
I close the door behind me, the click sounding final. I suppress a shiver as I turn to the Potions Master. "Sir, I have come for more Wolsbane Potion... if you have a new stock." I add quickly.
He nods and gets to his feet, holding out his hand expectantly. I pass the bag of empty phials over, and Snape sweeps to the corner of his office. After a few minutes, he returns, the bottles full of the potion again.
"Thank you, Sir," I say, taking the bag.
"You're welcome," Snape replies, heading back to his desk. I quickly leave; I know full well that the only reason Snape supplies me with the vital potion is because Dumbledore told him to.