戦場ヶ原ひたぎの計らいで阿良々木暦の家に身を寄せる事になった羽川翼。暦の家で一晩過ごした翼は、自分が昨晩「ブラック羽川」になっていた事に気が付く。
Part 4 of 5. The morning of August 24th. Not only Koyomi but also Suruga disappeared. Tsubasa realizes that she unknowingly turns into Black Hanekawa every night. Then, she comes across a vampire hunter Episode and a mysterious woman Izuko Gaen on the way to school. Izuko tells her that Tsubasa is going to name the Tiger as Kako. Meanwhile, Hitagi thinks that the fire follows Tsubasa.