Satsujin was a shy and kind high school girl that got killed on prom night by her partner. She got shot. She then turned into a ghost, and, being broken she, haunted the auditorium and killed anyone she saw was happy. Due to all the mysterious deaths after this, the school had to close down. (This is before Satsujin died and became an urban legend. Also, note, that she is not real, just an urban legend that the creator created for entertainment purposes. Happy Hanukkah!)