The Travelling Metamorphagus - Thrown Back In Time

After a drunken night, Tonks is sent back in time in Marauders' era with a strange box. Locked in a room with thirteen people, a few of them dead, a few totally different from their future selves and others plain strangers. To top that all, the box has a book. What would 14 seventeen year-olds trapped in a room with one book will do? Read it, of course! {Reading the books fic}