Buddy Daddies

Assassins Kazuki and Rei, while at a Christmas party, kill a human trafficking boss but are interrupted by a young girl who jumps into the scene calling him "Daddy". She is the boss's hidden child, 4-year-old Miri. Reluctantly, the two decide to live with and raise Miri, keeping her father's death a secret. They struggle to balance the demanding task of caring for a young child with their underworld jobs.

A year later, Miri's mother, Misaki, who has reformed, comes to take Miri back. However, Misaki is assassinated by a mafia hitman. Kazuki, who rescues Miri, considers placing her in a distant facility, but Rei opposes this idea. They decide to quit their criminal lives and leave the organization. On the day of the kindergarten Christmas party, Kazuki and Rei confront Rei's family's organization and declare their disassociation.

Years later, Kazuki and Rei run a diner in a coastal town and live as a family with Miri, who is now a high school student.