Bunta Kise arrives at Harunoya Inn with his wife Torako Kise and young son Shota Kise, seeking the healing waters to aid his recovery from traumatic injuries sustained in a car accident that left him comatose. He has black hair and grey eyes. During his stay, his dissatisfaction with the inn's bland cuisine prompts another guest to seek flavorful alternatives for him.

A pivotal revelation discloses Bunta as the comatose driver of the truck that collided with and killed the parents of protagonist Okko, an accident that claimed the other family and left only their daughter. Overwhelmed by guilt upon this discovery, Bunta prepares to abruptly depart with his family. However, Okko upholds the inn's principle of rejecting no guest and invites them to stay.

Bunta's presence and the revelation catalyze Okko's confrontation with her unresolved grief and trauma. His character arc embodies themes of forgiveness and the intertwined healing journey for both perpetrators and victims of tragedy.