Eat, drink and be merry (слэш)

This story will be rewritten someday in order to make my sense of humour less lame and pathetic.
I know I could just delete it instead of rewriting it, and I might well do that if I decide it’s a lost cause.
 
Headmistress Minerva has come up with what she thinks is a great idea to introduce the Muggle custom of Secret Santa at Hogwarts. It would be really fun if we randomly assign people to get each other gifts, wouldn't it?
Severus isn't entirely convinced. Having no choice, he agrees to take part.
 
Fanfic theme is gingerbread.