Nanatsu no Maken ga Shihai suru

Kimberly Magic Academy accepts new students with the understanding that many of them will never live to graduate. Oliver Horn forms a close group with Nanao Hibiya, a samurai whose instinctive swordsmanship is frighteningly natural, and four other first-years after an early incident shows them how dangerous the school really is. Classes can permanently alter body and mind, while a labyrinth beneath the campus punishes careless curiosity. Oliver appears disciplined and polite, but he entered Kimberly for a purpose his friends do not know, one tied to teachers who treat student lives as expendable. Friendship gives him something worth protecting, yet fulfilling his hidden goal will lead him toward forbidden secrets and the spellblades that cannot be used without a price.