It has been several years since Principal Celestia lost her wonderful family in a terrible accident that resulted in the disappearance of her only daughter. Several years of guilt and sadness took their toll on several of those closest to her, including her husband, but somehow she was able to overcome it. When a young girl forced her way into her office, begging to be enrolled, she thought it was just a cruel joke of the world, God or any force majeure. Especially when that girl turned out to be a tormented villain from another universe. But could Celestia's mistake be another girl's salvation?
(Because of the death tag, because there are going to be assassination attempts and supposed deaths.)