When she went back in time to save her lover, Kurohime made a shocking discovery: Zero had a younger brother, Rei! But before she can discover the nature of their relationship, Kurohime and the boys are trapped in a colossal prison, where gangs of howling convicts fight to kill them, and hordes of undead live within the walls. Can they escape this terrible place? Meanwhile, an old ally... or someone they thought was an ally... reveals his shocking true form!
Story and art by Masanori*Ookamigumi*Katakura.