Movie
Description
Jinnosuke Mudo is the biological father of the Nakano quintuplets. He is a middle-aged man, easily identified by his bald head and full white beard. Like his former wife, Rena Nakano, he worked as a teacher and was once her homeroom teacher and colleague.

Jinnosuke's personality is layered and ultimately self-centered. On the surface, he can appear gentle and calm, but he consistently reveals a deeply egocentric nature. His actions are driven by a desire for atonement. After years of being absent, he reappears claiming to regret abandoning his family and expressing a wish to make amends for his past sins. However, this pursuit of redemption is undercut by his behavior, as he frequently makes insulting remarks about his late wife, Rena, and criticizes the quintuplets' stepfather, Maruo Nakano, declaring him unfit for his role. This hypocrisy ultimately exposes his failure to take genuine responsibility for his own actions.

The character's backstory is central to the family's history. As soon as he learned that Rena was pregnant with quintuplets, he disappeared and was untraceable. He abandoned his pregnant wife to raise their five daughters alone, a decision that had a profound and lasting impact on the family. During his absence, he worked as a traveling lecturer, all the while claiming to have thought of his daughters.

In the story, Jinnosuke serves as a direct antagonist to the family's hard-won peace. He reappears during a critical time, seeking to reconnect with the quintuplets. His key relationships are defined by conflict. He holds animosity towards Maruo Nakano, blaming him for allowing the quintuplets to follow the same "misguided path" as their mother. His interactions with his daughters are tense and emotionally charged. In a notable confrontation with Itsuki, he attempts to pressure her into rejecting her mother's influence, even performing a dramatic act of contrition by slamming his head on the floor until it bled.

His role culminates in a final confrontation at the school festival. Unable to accept his daughters' rejection of his interference, he is formally disowned by Itsuki and Maruo. After being told to leave, Jinnosuke snarls at the family and departs, never to be seen or heard from again. Jinnosuke possesses no special abilities; his primary impact comes from his function as a disruptive figure whose return forces the family to confront the pain of their past.
Cast