I predict that Professor Lupin is Peter Pettigrew just in disguise. I predict this because, Professor Lupin is always trying to help Harry Potter as much as he can. With Sirius Black on the loose there are Dementors everywhere in Hogwarts, when ever Dementors are near Harry Potter, Harry always gets ill and faints which makes it very hard for him to do school and participate in his quidditch games. Due to all the Dementors who roam Hogwarts, Professor Lupin felt the need to take time out of his day every week to help harry learn how to cast spells that will make the Dementors disappear when they are near Harry Potter. Harry's friends, Ron and Hermione were in Hogsmeade, Harry was not aloud to go because he did not have his permission form filled