Flag. 1.0 When the Sun Goes Down

Keima explains to the audience how he has captured fourteen girls and two unique girls after the last season. Meanwhile, Kanon is preparing for her school tests, but ends up talking with her split personality, Apollo, who claims to be a goddess. The next day, Keima and Elsie meet up with Tenri and within her, Diana. Diana wants Keima to marry Tenri as Tenri's love for Keima increases her powers, which he refuses. When asked to explain what she is, Diana reveals she is a goddess, one of the Jupiter Sisters, who helped the New Demons of Hell against the Weiss, when they attempted to take over the three realms of Earth, Heaven and Hell, and control all souls. After defeating them, the Jupiter Sisters sacrificed themselves by sealing themselves together with the Weiss, but they escaped ten years ago. Diana asks Keima to help find her sisters and reveals they reside in his past conquests, who did not forget their memories with him.