Katsuya Honda is Tooru's late father. He used to be a student teacher when he met Kyouko Honda who he helped leave her previous lifestyle.
He later left student teaching and married Kyouko, despite the eight-year age gap. When he and Kyoko met, she was 13, and he was 21. Katsuya, who had apparently had a rebellious childhood, admitted that he had fallen in love with Kyouko because she had been able to cry and confess to being lonely, which he wasn't able to do. When Kyouko told him she was pregnant and had doubts as to whether she could properly raise a child, he assures her that they will take care of the baby together, as a real family. A short time later, when Tohru was three years old, he died of pneumonia. The sudden death caused Kyouko to almost kill herself.
