The Farthest Galaxy(最も遠い銀河)

Detective Seiichiro Watari is nearing retirement, but is still bothered by an unsolved case from seven years ago when the decomposed corpse of a female was found by a fisherman in the sea of Otaru. The body was never identified so the case was never solved. Three years after his retirement, Watari unexpectedly discovers a clue that may finally solve the case.