Ciro Valentin had one mission: seal the castle and call the Department of Magical Accidents and Catastrophes to hide the big fucking thing. Instead he goes exploring, awakens an old scary evil (with a nose), and winds up around forty years in the past.

At least Dumbledore has his hobby of studying wonky wizardry, so all Ciro has to do in the meantime is sit back and wait for a solution to present itself on a silver platter.

...What's this about a teaching position?

SIOC. Time-Travel. DADA teacher. Marauders era.