demon hunter at hogwarts

Introduction: One year before Harry Potter entered school, Regulus Black, who was supposed to sleep at the bottom of the lake, reawakened due to mysterious power.Those once destined fates have become confusing again. "Regulus, you sacrificed everything, but I didn't do anything..." "The Sirius in my impression is not a mother-in-law. Use your energy to break up with the family and send the Dark Lord to hell. ." "Huh, of course I will do that... Any other parting words?" "If we never see each other again, then I wish you a worthy death." "To each other."