Years ago, Kazuki was excited to find out he was going to become a father, but his job forced him to take another path in life.
Later, Kazuki still regrets what happened at that stage of his life, and now fully dedicates himself to his job as a hitman.
And despite his way of living, Kazuki does not neglect the details of his life, including cleaning his apartment, as well as feeding his partner Rei, who is a complete disaster at home, but during his missions turns out to be a ruthless assassin.
One day, Kazuki receives orders to intercept a new target, and begins to research enough information to allow them to do the job.
He finds out that the man is having a big party at a fancy hotel, and that his wife is really picky with details. Thus, Kazuki decides to make use of such obsession and prepares his entrance to the party carefully.
Kazuki is no less detailed, and begins to bake a cake worthy of a tycoon, or a criminal leader. Gets an employee access and dresses up according to the occasion, Santa Claus, after all it’s Christmas.
At the building, Kazuki is surprised to see that a 4-year-old girl, Miri, following closely behind him, and despite security, she jumps in the same elevator as him, and as she stares at the cake, the girl tells him that it must be delicious.
Kazuki lets her taste the cake, and it doesn’t take long for him to get excited when he sees how she enjoys the dessert he prepared with such care. Suddenly, Miri asks Santa if he will grant her wish to see her father.
Kazuki allows Miri to eat her cake as they go up to the floor where the party is taking place. And as soon as they arrive, the little girl runs off looking for her father.
As the security guards try to stop the girl and Kazuki, Rei appears and doesn’t hesitate to fire his gun.
The party is over, and everyone begins to flee the place, while Rei searches for her target, Kazuki watches in alarm as Miri approaches their target and he does not hesitate to take her hostage.
Kazuki yells at Miri that he found her father, and as he takes off his Santa costume, he assures her that it’s him. Miri doesn’t hesitate to throw herself into his arms, while Rei finishes their work.
Later, when they go through Miri’s belongings, it turns out that her mother purposely sent her to meet her father, who ends up being the same man who was just terminated.