Hou Ken is a central antagonist in the story, recognized as one of the State of Zhao's Three Great Heavens and a figure of immense martial power known as a Bushin. His origin is rooted in tragedy; as an infant, he was kidnapped by a Bushin who slaughtered his parents, benevolent chi healers. This captor raised him through brutal, isolated training in the mountains, forging him into a warrior who would eventually bear the same tattoos, wield a similar glaive, and wear nearly identical attire to his master.

Driven by a singular obsession, Hou Ken considers himself a failed Path Seeker, a disillusioned quest for martial divinity that was shattered by his first defeat at the hands of the Qin general Ou Ki. This event transformed him from a detached seeker into an entity of vengeance. He is ruthlessly pragmatic, believing himself to be the sole being feared by the heavens. He is acutely sensitive to the martial potential in others and is willing to kill even children, like the young Shin and Kyou Kai, if he perceives them as a future threat. His presence alone inspires paralyzing fear in ordinary soldiers, and he speaks in an archaic manner, often using terms like "thou". Despite his solitary and inhuman demeanor, he maintains a complex alliance with the Zhao strategist Ri Boku. After a fateful first meeting where Hou Ken sensed a destined connection, he came to view Ri Boku as a guide who could lead him to the "Answer" he sought, allowing himself to be drawn into the affairs of the warring states.

Within the larger conflict, Hou Ken serves as a nearly unstoppable enforcer for Zhao, sent to eliminate high-value targets and turn the tide of battle through raw, overwhelming force. His role in the story is defined by a series of legendary duels. He first emerged from training to answer the challenge of Kyou, one of Qin's Six Great Generals, whom he killed in combat. Though grievously wounded by her enraged comrade Ou Ki, who carved the infamous scar across his face, Hou Ken survived and spent years training for a rematch. Years later at the Battle of Bayou, he confronted Ou Ki again. Their duel was a stalemate until a stray arrow struck the Qin general, allowing Hou Ken to deliver a fatal blow, though he himself did not feel like the victor and retreated to train further. He re-emerged to kill Yan's Great General Geki Shin in a single day and, during the Coalition Invasion, slew the fierce Duke Hyou. Throughout these encounters, an ideological conflict emerges: warriors like Duke Hyou recognize that Hou Ken, for all his physical perfection, is a "buffoon" who cannot comprehend the strength and "weight" that men derive from the bonds of comradeship and the will of fallen allies.

Hou Ken's development is one of gradual, fatal disillusionment. His quest is to prove his superiority and justify his path, yet he is repeatedly stymied by those who fight for something other than simple martial supremacy. His primary ability is his superhuman combat prowess. His strength is monstrous, capable of cutting through multiple armored soldiers with a single swing of his glaive, crushing enemies, and throwing a spear with enough force to kill three men. Despite his massive frame, he possesses immense speed and reflexes, allowing him to match the lightning-fast techniques of Kyou Kai and block volleys of projectiles. His endurance and durability are equally remarkable, having survived a volley of arrows, a fall from a cliff, and repeated near-fatal wounds from the world's strongest fighters. As a Bushin, he is also capable of manipulating chi, using it to enhance his physicality, heal his wounds, and disrupt the internal organs of his opponents. Hou Ken's path culminates in his final battle against Shin, the young warrior whose potential he once dismissed. In their duel, Shin channels the collective will of his fallen comrades, a weight of human emotion and resolve that finally overwhelms Hou Ken's isolated and purely physical might, leading to his death.