Tsukidate no Satsujin

Sorami Karigaya, a high school student in Okinawa, has recently lost her mother and is still grieving the death of her father from years prior. Two months after her mother’s passing, an attorney from Hokkaido visits her to address inheritance matters concerning her maternal grandfather, a man her mother had claimed was long dead. The attorney reveals that her mother had concealed the grandfather’s existence out of deep resentment toward her own father. To resolve the inheritance issue, Sorami must travel to Hokkaido, but the attorney adds a condition: her grandfather can only be contacted via the express train Genya, a mode of transport her mother had strictly forbidden her from using.