Lonely Castle in the Mirror (Manga) Vol. 2

More about the book

A group of seven junior high students, all of whom don’t attend school, discover a mysterious castle that serves as a refuge for some, like Kokoro, but not for others. Tensions rise when Ureshino decides to return to school and comes back with unexplained injuries. As the summer ends, personal secrets begin to surface among the group, leading to a pivotal announcement from Ookami-sama that introduces a new rule, altering their dynamics and the nature of their sanctuary.