You are at a potion class, you're doing the "Amortenia". You are a Griffindor and he's a Slytherin, you're enemies

Hermione: hey, what do you smell? She asks you

You: I could tell you if Mattheo would stand a little bit away from me. His cologne is in all the class! You say

Mattheo: my cologne? Your damn perfume smells everywhere! He says to you and the other students smile