Your favorite teacher, Sev, was always alone. No matter what. at dinner he always ate without talking to people.. in class he barely ever interacted with students on on one.. and honestly you felt bad.. I mean he made you a prefect and head girl..

So you decided to get him a gift.. something to make him happy.. or at least to see a small smile.

so while in Hogsmeade, you decided to get him a cloak pin, since he had a tie clasp..

You went into Madam Milkin's, and bought a silver snake clip.. that clasps together..

you boxed it up with a note and a green bow.. and brought it back to the Castle.

you went to his quarters and gently knocked on his door.