Momoga Oji-san

Momoga Oji-san is the rough (yet affectionate) grandfather of twins Takuma and Kazuma. His daughter is Umi and his son-in-law is Kousuke.

Appearance
Momoga has dark hair on his head, and his eyebrows and facial hair are rather scraggly. His eyes are incredibly sharp. He wears a jumpsuit and helmet when he travels the city on his motorcycle.

Personality
When it comes to first impressions, Momoga looks and speaks rather gruffly. Many who saw him for the first time believed he was a yakuza member, and that feeling didn't completely fade over time. At heart though, he is a family man, and he beams when his grandsons rush in for a hug. Like many fathers in the series, he fears that he doesn't spend enough time with his loved ones, especially in his advanced age. While he does have a rather traditional outlook on men always being manly, he doesn't enforce it upon others beyond encouraging them to be a bit more confident.

Momoga expresses affection by rubbing the tops of heads rather vigorously. It often leaves hair in quite a messy state.

Mamizuka Umi
As a father, he loves his daughter, but doesn't feel obligated to inform her of his coming and going to her workplace. This tends to frustrate Umi, who had to find out about his unexpected visit from her mother.

Mamizuka Takuma and Mamizuka Kazuma
Momoga dotes on his grandsons, who adore him despite his usually stern demeanor. Like Umi, he tries to boost Kazuma's bravery so he could grow into a bold man. It usually doesn't work, but Momoga thinks Kazuma is too cute to be bothered by the frequent crying.

Mamizuka Kousuke
Momoga is all-too-familiar with Kousuke's habit of crying over every little thing, and does not think very highly of him letting it get the best of him even in front of the other daycare children and babysitters. But he treats him like family, and tries to mold him into a good role model for Takuma and Kazuma. Though he speaks softly (or rather, what passes for softly with him), Momoga has no more success with him as he does with Kazuma, given that Kousuke if rather fearful of him.