Saigo no Seifuku

Saigo no Seifuku summary:

The Last Uniform, also known as Our Last Season, is about a girls' boarding school. The school is in decline, with thirty-two of the fifty rooms in the dorm left empty. Nonetheless, the school's rules are unchanging and absolute. One of the rules is "room sharing," that is that each room in the dorm is meant for three people and there must be three people to a room, regardless of how many rooms are left empty in the school's current state. This is the story of the girls in that school.