Danganronpa Another Episode: Ultra Despair Girls

Komaru Naegi, little sister to Makoto Naegi, has been imprisoned inside a mysterious apartment for over a year. One day, she is rescued by Byakuya Togami of Future Foundation, but the rescue is derailed by a sudden attack of hundreds of Monokumas. Komaru soon discovers that the city has been taken over by a group of children calling themselves the Warriors of Hope. Their leader, Monaca, declares that the city will be the site of a “children's paradise,” and to accomplish this, all the adults will be exterminated.