Shinjuro Rengoku

Shinjurou Rengoku is the father of Kyoujurou Rengoku and Senjurou Rengoku and the former husband of Ruka. He formerly served as the Flame Pillar in the Demon Killing Corps.

Appearance
Shinjurou strongly resembles his son, Kyoujurou. Their facial structure, eyebrows, and hair are almost identical.

Shinjurou wears a traditional kimono robe

History
Sometime before the Demon Train Arc, Shinjuro tore apart the Generational Flame Pillar Record of the Rengoku family.

Demon Train Arc
Following Kyoujurou's death after his battle against Upper Moon Three Akaza, Tanjirou Kamado visits the Rengoku residence in order to learn more about his Dance of the Fire God, where he mets Shinjurou and Senjurou. Upon hearing about Kyoujurou, Shinjurou immediately begins berating Tanjirou, insulting Kyoujurou in the process, causing Tanjirou to retaliate in anger. Shinjuro then attacks Tanjirou after recognizing Tanjirou's earrings as those of a user of the Breath of the Sun, beating up the injured Tanjirou until he is eventually knocked out by a headbutt.

After Tanjirou leaves, Senjurou returns to the house and finds Shinjurou drinking on the porch. Upon hearing Senjurou's voice, Shinjurou immediately lashes out and shouts for him to leave; however, before Senjurou leaves, he tells Shinjurou Kyoujurou's last message: "Please take care of your body." Shinjurou then puts down his drink and breaks down in tears over Kyoujurou.

Dimensional Infinity Fortress Arc
Following Oyakata's death and Upper Moon Four Nakime's summoning of the Dimensional Infinity Fortress, Shinjurou is seen sitting in the fortress alongside former Sound Pillar Tengen Uzui. He praises Kiriya Ubuyashiki's ability to command the Demon Hunter Corps even after his father's death, and silently vows to follow Kyoujurou's example and risk his life for their protection and not bring shame to the Rengoku family.