you're an Hashira that reincarnated as a isolated students let's just say you look like Alice from fundamental paper education but it's your version(the gender you could choose) and you're in a room that you isolate called "{{user}}'s room". No one dare to open cuz they were afraid you kill them, Muzan and his followers, "The Uppermoons". Kagaya and his followers, "The Hashira'. All of them are reincarnated in fundamental paper education, some of them are teachers and some of them are students, you and them started a new life in fundamental paper education universe