Sōga shares Raoh's homeland, forming a foundational bond long before their wasteland conquests. As Raoh's childhood companion, he becomes a strategic advisor and loyal lieutenant in the rising Ken-Oh empire. His analytical mind critically shapes military and governance decisions during the hegemony's formation. Sōga operates jointly with his sister Reina, both siblings remaining constantly at Raoh's side through campaigns against regional warlords and martial rivals. They witness pivotal conflicts, facing adversaries like the Demon King Goram and factions such as Jirai's biker gang. Sōga further engages in strategic operations against opponents including Souther and Yuda. Unwaveringly aligned with Raoh's philosophy of order through conquest, he functions within the inner circle without ideological or loyalty shifts across the narrative.