After a failed dream pursuit, Nagomu Irino returns home upon learning of his father's hospitalization, concerned about the future of their Kyoto sweets store. To his surprise, his father has already chosen a successor in the form of 10-year-old Itsuka Yukihira, abandoned at Ryokushou and searching for her missing father. Tasked by his mother to support Itsuka, Nagomu steps into the role of a father figure, leading to a transformative journey where they bond over their shared passion for the family business and sweets, gradually bridging their initial differences and spreading a little sweetness in their intertwined lives.