Kazuma took Kyo in as an adoptive father after Kyo's mother's suicide, partly out of guilt—as a kid, he'd been cruel to his own grandfather simply because the cat curse made him an outcast in the Sohma family. He wanted to make up for that. He's Kyo's martial arts instructor and father figure, and Kyo calls him Shishou (master). Beyond Kyo, Kazuma has trained several other Sohmas in martial arts, including Kagura, Yuki, and Haru.
He's protective of Kyo's wellbeing and genuinely cares about his relationship with Tohru, hoping her feelings are real and that the two won't end up repeating the painful dynamic of his own grandparents.
Content compiled by AnimeList.moe from publicly available sources.
