The Night Beyond the Tricornered Window, Volume 3 (The Night Beyond the Tricornered Window #13-18)

Erika Hiura leads a strange double life as both a normal high school student and a secretly powerful necromancer whose services are sold to the highest bidder. Her interest in exorcist odd couple Hiyakawa and Mikado seems innocent, but when they’re called in to investigate a missing-persons case, the connections between the three may be deeper than any of them realize. Meanwhile, the relationship between Hiyakawa and Mikado continues to evolve in ever more intimate, and disturbing, directions.