Suruga Kanbaru starts her senior year at Naoetsu High without her upperclassman Koyomi Araragi, who has graduated and moved on. When rumors surface about a wish-granting 'Devil' working out of the town, Suruga fears her own monkey's-paw curse may have spawned a new aberration. She tracks the rumor to Rouka Numachi, a former basketball rival sidelined by a leg injury, who has been collecting other people's misfortunes in exchange for hollow promises.