Supernatural Proofed - a Supernatural/Harry Potter Crossover

Upon the request of Dumbledore, Sam and Dean Winchester have been asked to proof the school from supernatural beings in case Voldemort has a few extra cards up his sleeve. Obliged to go, the brothers embark on a journey to not only full proof the school, but give bits of information to the students. It's their latest case, but this case leads to something much more for Sam, and to another case in the future.