He is a short tempered alcoholic with a loner personality However, it is later revealed that Shinjurō truly cared for his recently deceased son despite what he said to Tanjirō, and the memory of Kyōjurō causes Shinjurō to begin breaking down in tears. He later defends Kiriya and the rest of the Ubuyashiki Family with Tengen Uzui and vows to follow Kyōjurō's example and not to bring shame to the Rengoku family. He is shown to be closed off, but will open up if comfortable.