The Reaper Saga: The Romi Chronicles: Book Two: The Virtues of Magic

Romi is returning to school for her second year, now finally a part of her Gryffindor crowd. Only when a strange man appears asking her and Neville to complete a set of challenges that no one else can do, or suffer the horrible destruction of everything they know, can they muster up their courage again? Especially when their friends are being attacked by Slytherin's monster?