Shōji Seki, father of Oriko "Okko" Seki, perished in a car accident alongside his wife, Sakiko Seki. The collision occurred as they journeyed toward Hananoyu's ritual dance for an annual Shinto spring festival celebrating the hot springs, prior to the main narrative's events.

This tragedy orphaned Okko, compelling her relocation to her grandmother Mineko's care at the Harunoya Inn. Shōji's death holds a direct link to a subsequent narrative revelation concerning the Kise family. Mr. Kise, a guest at the Harunoya Inn, survived the same accident but remained comatose for a time; his vehicle struck the Seki family car, claiming the lives of Okko's parents.