Yōsuke Hitsujitani serves as a young male member of the Grand Paladin organization. He prefers indoor settings and is perceived as less capable in combat than his peers, leading other Grand Paladin members to frequently assign him tasks or take advantage of his perceived weakness.

His long-standing friendship and operational partnership with fellow member Benika Takatori form a key aspect of his background. This established bond proves crucial when both defect from Grand Paladin to join the antagonistic Sealing Faction under Generalissimo.

Following their defection, Yōsuke arrives at the seal of the Nebula government alongside Harumi Kumashiro and Benika. There, Benika recounts her motivations for joining the Sealing Faction, framing their shared decision to leave Grand Paladin. His Nebula Weapon features a sheep motif, aligning with the animal themes of Grand Paladin members and reflecting the meaning of his surname "Hitsujitani," which incorporates the Japanese word for sheep.