Hayate X Blade (manga)

Anime News Network Plot Summary: While Hayate Kurogane's twin sister Nagi is recovering from an injury, Hayate must take her place at Tenchi Academy. The academy is an all girls' school that teaches regular classes as well as "Sword Arts". In Sword Arts, students attempt ... http://www.animenewsnetwork.com/encyclopedia/manga.php?id=6025