Born with the rare ability to absorb vast quantities of Altana, a planetary energy, Utsuro gained near-ageless immortality and powerful regeneration, healing rapidly from any wound. This immortality sparked persecution by fearful humans, trapping him in a vicious cycle of suffering through repeated attempts on his life. Unable to endure constant torture and death, he fractured psychologically, developing multiple personalities as a defense. Forgotten in imprisonment for decades, he escaped when his cell door rotted. Violent personas seized control after his escape, driving him to become a serial killer consumed by revenge and a desperate desire to regain humanity. Captured by the imperial government, his perceived utility spared him execution. He was instead made an assassin and founded the Tenshouin Naraku, an elite assassination organization he commanded for roughly 500 years. During this era, he continued killing while nurturing a profound death wish. His original personality, observing the violence from within, created Yoshida Shouyou—a distinct persona designed to resist the bloodshed. Shouyou defected from the Naraku, took in orphans like Gintoki Sakata, and founded a school dedicated to peace. Despite this pursuit of non-violence, Shouyou's location was betrayed, leading to his arrest and the school's destruction. During Shouyou's execution, the original personality reasserted dominance, eliminating all other personas, including Shouyou, to become the sole consciousness. He adopted the name Utsuro, meaning "emptiness." Revived before former Naraku subordinates, he joined the Tendoshuu, a council of powerful Amanto leaders, offering his immortality research in exchange for their aid in finding death. His backstory culminated in a plan to end his suffering by destroying Earth and the universe. He manipulated the Harusame pirates into revolting against their leaders, framed the Tendoshuu for overloading Altana cores to annihilate multiple planets, and incited universal war. His final aim was to use a planet-destroying cannon to trigger Earth's destruction, releasing enough Altana to erase the cosmos. Utsuro's personality mirrored his name, often described as an empty vessel. He exhibited emotional detachment, a consequence of enduring centuries of persecution and violence. His core motivation was an all-consuming death wish, driving him to seek opponents capable of killing him, such as Umibouzu. Later, he revealed a ruthless, psychopathic side, taking glee in destruction and taunting enemies. Despite hating humanity, he harbored jealousy and fear toward them, contributing to his creation of the Shouyou persona. His actions displayed extreme sadism, remorselessness, and a god complex, viewing all life as hollow and meaningless. His physical abilities included master-level swordsmanship, recognized by characters like Sougo Okita for its resemblance to Shouyou's style, and expertise in Hakkei—a martial art employing explosive inner energy strikes. His combat prowess enabled him to battle multiple powerful opponents simultaneously, including Gintoki, Kagura, and Nobume. His immortality rendered him immune to disease, poison, and aging, with rapid regeneration healing even beheading or incineration. He could share his blood to grant quasi-immortality, though it caused gradual bodily decay and allowed him to possess recipients. His strategic cunning was evident in manipulating factions like the Tendoshuu and Harusame, exploiting their desires for immortality or power to advance his universal destruction scheme. Key relationships defined his narrative. Oboro, his first disciple, received his blood as a dying child, becoming a semi-immortal loyal follower who later betrayed Shouyou. Nobume, a former Naraku member, became his enemy after defecting and identifying him as the universe's most dangerous entity. Yoshida Shouyou represented his suppressed goodness, though Utsuro destroyed this persona during the execution. This act retroactively complicated Shouyou's legacy, as Shouyou's earlier noble deeds—like protecting students—were reinterpreted as part of a plan for his disciples to eventually defeat Utsuro, raising questions about his responsibility toward them. Utsuro's defeat involved physical and ideological confrontation. After possessing Takasugi Shinsuke's body in a final attempt to kill the re-emerged Shouyou consciousness, he was fought by Gintoki and allies. During this battle, he realized his philosophy of universal emptiness was flawed: though people are hollow, they fill their emptiness with connections to others. This realization, coupled with sustained combat, led to his demise. His death was portrayed as straightforward, achieved through force after his ideological basis collapsed. Narratively, Utsuro's introduction recontextualized key events. It retroactively framed Shouyou's adoption of Gintoki as a means to forge a weapon against Utsuro, altering Shouyou's perceived selflessness. His late-series introduction and Altana-based abilities were noted for creating plot conveniences, such as unexplained possession or reincarnation mechanics. Furthermore, his role as the final antagonist shifted focus from Gintoki's personal consequences for killing Shouyou to a broader, impersonal conflict, diminishing the emotional weight of earlier character struggles.