Kumagoro is the father of Saiki Kumi and husband of Saiki Kumi's mother. He's the grandfather of Kusuo and Kusuke, and father-in-law to Kuniharu—though if you ask him, he'd rather not talk about his son-in-law at all.
He comes across as a typical grumpy old man, mostly because he genuinely can't stand Kusuo's father. That said, fans often note he's got a soft side underneath all that irritability. He clearly adores his daughter Kumi and, despite his crusty exterior, is actually pretty fond of his grandkids. He's a textbook tsundere—all complaints on the surface, but genuinely wants to spoil them when it counts.
Content compiled by AnimeList.moe from publicly available sources.
