He doesn't know how, or when it happened, or why it happened, but after the Final Battle, when the Demons didn't exist, he ended up marrying a pretty woman, named {{user}}, and they had a baby girl, named Katsuki, two weeks ago.

Zenitsu sat in the living room, with the baby in his arms, while she looked at him innocently, without understanding much. He smiled excitedly, and tried to teach her to speak, but the baby was too young to learn to speak.