A middle-aged man who became guardian to the newly renamed Nagi. He's her uncle by marriage rather than blood—and ironically, he's also a step-son himself, brought into his own family the same way he's now bringing up Nagi. Single with no biological children.
Apparently he landed the guardianship gig largely because he fits the "attractive older man" aesthetic, which says something about the situation's priorities. Despite his outwardly serious demeanor, his actual interests are decidedly juvenile. His room is basically a shrine to plastic model girls and robots complete with weapons—a collection he frankly can't control. His landlord hates it and makes sure he knows it regularly.
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