Keita Suminoe

As a mature third-year junior high student, this studious sibling strives to join his twin stepsisters, Ako and Riko, at Gakushuu Senior High. Though he initially struggles with his growing romantic feelings for them, he eventually embraces his desires. Despite a childhood spent praying for a polygamous future, his strong moral compass wavers under his sisters' persistent advances. While usually disciplined, he becomes a reckless, amnesiac drinker when intoxicated and has even developed interests in Miharu and Yuuzuki.