On Christmas Eve in snowy Tokyo, three homeless outcasts—Gin, an alcoholic former bicycle shop owner; Hana, a compassionate transgender woman; and Miyuki, a runaway teenager—discover an abandoned newborn girl in a pile of garbage. Hana, yearning to be a mother, names the baby Kiyoko, meaning "pure child," and convinces the reluctant Gin and Miyuki to help find her parents. Despite their freezing conditions and gnawing hunger, the trio embarks on a bizarre urban odyssey driven by the baby's safety. Their first major lead comes from a key left with the infant, which leads them to a locked locker containing a mysterious bag. Inside, they find a wallet, a bar receipt, and a photograph of a man. This clue points them toward a wealthy restaurant where a wedding is taking place. While attempting to return the items, Hana is attacked by a gang of hostile youths, leading to a frantic chase through the neon-lit streets. The confrontation is abruptly halted when Hana collapses from exhaustion and her worsening health. Nursed back to health at a friendly stranger’s restaurant, the group eventually tracks down the address from the wallet, only to find the apartment ransacked and the father, a man named bridegroom, apparently dead from an apparent suicide. Grief-struck, the trio's morale shatters, and old tensions flare. Gin is haunted by his painful past of abandoning his family after losing everything to gambling, while Miyuki struggles with the guilt of stabbing her abusive father. Amid these escalating emotional crises, a mysterious hitman accidentally shoots Hana during a chaotic street encounter. While visiting Hana in the hospital, Miyuki and Gin encounter a frantic mother who confesses to abandoning Kiyoko out of extreme poverty and postpartum depression. To complicate matters, the baby is kidnapped by the desperate hitman, who turns out to be the deranged, grieving father of the infant, threatening to jump off a high-rise building with the child. Risking their lives, Gin and Miyuki scramble to the rooftop. Gin climbs the ledge and exposes his own past failures to empathize with the distraught man, ultimately talking him down and safely rescuing the baby. In the heartwarming aftermath, the
biological parents are reunited with Kiyoko, promising to start anew. Meanwhile, the eccentric trio’s bizarre holiday adventure inadvertently helps them confront their own personal demons. Miyuki finally calls her
estranged father to reconcile, and Gin takes steps to reconnect with his adult daughter, proving that even on society's coldest fringes, miraculous bonds of chosen family can heal the deepest wounds.