One festive Christmas Eve, after enjoying a delightful children's nativity play, three homeless individuals stumble upon a shocking discovery—a newborn baby amidst the trash while scavenging for gifts. The group comprises a middle-aged alcoholic named Gin, a former cycle racer who faced a downfall due to gambling debts and a ban from his sport, a vibrant transgender woman named Hana, and a troubled teenage runaway named Miyuki. Alongside the unnamed baby is a note beseeching the finder to care for the child, accompanied by a bag filled with clues hinting at the parents’ identities. In a moment of epiphany, Hana believes the baby is a divine gift, deciding to become her protector.
They name the baby Kiyoko, which translates to "pure child" in a heartwarming nod to the night of her discovery. As they delve deeper, the trio finds a locker key among Kiyoko's belongings that leads them to a railway station. However, their quest is interrupted by heavy snowfall, causing train delays. In a moment of desperation, Miyuki escapes through a window and spots her father on a train that halted next to theirs. Hana and Gin follow suit, leading them to seek shelter in a nearby cemetery.
Fate intervenes as they encounter an influential Yakuza boss trapped under his own vehicle. Coincidentally, he is familiar with the owner of a club where Kiyoko's mother once worked. As their journey unfolds, they attend a wedding reception at the club, where the groom reveals that Kiyoko's mother is a past bar girl named Sachiko. However, the celebration turns chaotic when a disguised hit-man attempts to assassinate the bride’s father, resulting in a kidnapping that drags both Miyuki and Kiyoko into peril.
In a tense situation, Miyuki forges an unexpected bond with the hit-man's wife, who has her own child. Amidst their unfolding drama, Miyuki confesses to her past trauma involving her overbearing father, which fueled her runaway life. Meanwhile, Gin tries to care for an elderly homeless man who dies in front of him, and shortly after, they find shelter at a club where Hana reflects on her life’s misfortunes, including a past assault that led to her homelessness.
Their quest continues only to find Sachiko’s former home demolished, learning of her troubled relationship with a husband plagued by gambling issues. They narrowly escape disaster after an ambulance crashes into the store where they sought refuge. This near-death experience cements Hana’s belief that Kiyoko is a divine messenger sent to protect them.
At the hospital, Gin encounters his estranged daughter, also named Kiyoko, stirring up conflict when Hana berates him for abandoning his family. The tension rises when Hana and Miyuki find Sachiko on the verge of a tragic decision by the bridge, claiming a lack of knowledge regarding Kiyoko’s kidnapping from the hospital. As they scramble to rescue Kiyoko, a frantic chase ensues, unfolding long-buried family trauma and desperate choices.
In a dramatic culmination, Sachiko's misguided intentions lead to a perilous standoff atop a building, where the estranged couple’s long-neglected feelings resurface amid a harrowing climax. Despite the chaos, a miraculous wind allows Hana to save the baby, and all three homeless souls find themselves in the hospital once more, only to discover an unexpected twist involving a winning lottery ticket left by the deceased elderly man.
Ultimately, Kiyoko's biological parents wish to adopt the trio as her godparents, leading to an unexpected reconciliation as Miyuki’s father turns out to be the police inspector who introduces them to the couple, symbolizing a profound connection born from their shared struggles.
