He appeared halfway through the series when Nakago revealed that the Chiriko that the heroes found was Omiboshi. After Omiboshi is found out and falls into a river, Suboshi mourns for his brother.
Suboshi then decides to get "revenge" on the heroes and murders Tamahome's father and younger siblings. This enrages Tamahome who nearly kills Suboshi who escapes. Suboshi falls in love with Yui Hongo, the Priestess of Seiryu and warns her to be wary of Nakago.
Because he believed that Yui was raped, Suboshi harbored an intense hatred for Miaka. When Omiboshi is revealed to be alive, Suboshi kills Tomo for hurting his brother and erases his brother's memories so he could live a peaceful life. Afterwards, he sought to rape Miaka in retaliation for Yui, only to be chased off.
When Miaka and Tamahome are sent to the real world, Nakago sends Suboshi to help Yui. In full rage, Suboshi tries to kill Miaka even though Yui asked the Seiryu Warrios not to. Tamahome comes to Miaka's defense. Suboshi then uses Ryuseisui's most powerful ability, a ball that chases its target with high speeds, to kill Tamahome. Tamahome lures the ball to Suboshi. Before Suboshi can dodge it, the souls of Tamahome's siblings hold him down. the ball pierces Suboshi's heart, killing him. Omiboshi senses his brother's death but quickly dismisses it due to his memory loss. Suboshi's corpse fades away.