Koshiro and Nanoka's father. While he was married to Makie, he had an affair; it is implied that this was the cause of their divorce. A man in late middle age, he is prone to bouts of hysterical worry, and is somewhat clueless. Still, he cares for his children (although he clearly favors Nanoka) and does his best to make Nanoka feel at home in her new surroundings. He is an architect.