Yutaka Nakamura is the father of Kumiko.
Yutaka came to Springfield looking for his daughter's house and found in the address the Android's Dungeon & Baseball Card Shop. Homer bumped into him and accidentally spoke badly about Comic Book Guy, causing Mr. Nakamura to take Kumiko away from him.
Homer tried make things right and got drunk with him. His wife's ghost then appeared to him and got angry because they agreed to a double suicide. After drinking Snake Rice Wine, he and Homer hallucinated and saw lots of spirits in a homage to Hayao Miyazaki, including No-Face, who tried to take Kumiko away and then took off his mask, revealing himself to be Mr. Nakamura. He then realized that he was the actual monster and gave his blessing for Comic Book Guy and his daughter.
He then attended the wedding, where his wife appeared again as a ghost and told him that she was kind of happy.