The 6-year-old girl Lu Helin (voiced by Matsuura Ayumi) lost her favorite grandfather Song Yi (voiced by Arikawa Hiroshi). It is said that she is Song Yi's illegitimate daughter. This ambiguous identity has become a shame and burden for Lu He's family. But at the funeral, Rin met the most important person in her life-a 30-year-old single man named Kawachi Daikichi (voiced by Tsuchida Dai) from a clothing company. He is Song Yi's grandson. Faced with the little aunt who was rejected by her family, Daji resolutely took on the responsibility of taking care of Rin. For Rin, Daji changed his life, sacrificed his career and love, and accompanied her through countless ordinary years. As the "daughter" grew up day by day, the feelings between Daji and Rin deepened, and the ties in each other's hearts were irreplaceable... This film is adapted from the popular manga of the same name by Yumi Urita.