Synopsis

Detective Yumi Miyamoto, while reading a news report about the shogi championship, discovers that Haneda is a professional player. Years prior, she'd received a cryptic envelope from him, instructed to remain unopened until he achieved "all seven." Now, with Haneda having won all the major titles, Detective Sato surmises the envelope likely contains a marriage registration. However, Yumi had discarded the magazine in which she kept the letter that morning. They rush to the dump, but the magazin