Reunited with Siesta, Kimihiko is pulled back into action as assistant to the Ace Detective. Together, the two face off against Seed again and, with a little extra help, defeat him. Although that particular crisis may be over, the journey to awaken Natsunagi continues. In search of clues for how to save her, Siesta and Kimihiko travel to New York City. However, instead of answers, they find trouble brewing with the Phantom Thief—and worst of all, Siesta disappears!