Duty of an Host Club Advisor

Being the youngest and most successful businessmen in the world after he left the Wizarding World after the Battle of Hogwarts is not enough for one Harry Potter. He just had to make himself to be a teacher and the adviser of the Host Club of the School, hadn't he? He really should take that paid vacation. AU! an omake of LoliBat's amazing story, That Crazy Nut of a Teacher!