Sugimoto was born into a poor farming family in Japan and had a difficult upbringing. As a child, he learned how to fight and survive in harsh conditions, which later helped him during his military service in the Russo-Japanese War. His life took a tragic turn when his close childhood friend, Toraji, was drafted into the war. Toraji was married to Umeko, the woman Sugimoto secretly loved, making Sugimoto feel obligated to protect him.

During the war, Sugimoto proved to be an exceptional soldier, known for his fearless and relentless fighting style. However, after witnessing countless deaths, he became desensitized to violence, yet remained loyal to his comrades and driven by a sense of duty. After the war, he learned that Toraji had died, and Umeko was going blind, leaving him determined to find gold and support her. This led him to Hokkaido, where he heard about the legendary stolen Ainu gold and began his journey.

Sugimoto is a tall, muscular man with a rugged and battle-worn appearance. He has sharp facial features, a strong jawline, and thick eyebrows, giving him a tough yet determined look. His most distinguishing feature is the large vertical scar running across his face, a mark of his survival through countless battles.

He typically wears a military-style uniform with a yellowish-brown scarf, reflecting his background as a war veteran. His piercing eyes and intense expressions further emphasize his unbreakable will and fighting spirit.

Sugimoto is resilient, courageous, and fiercely determined, embodying the traits of a true survivor. Despite his brutal combat skills and unwavering resolve, he is not heartless he is deeply loyal, compassionate, and protective of those he cares about. His nickname, “Sugimoto the Immortal,” stems from his uncanny ability to survive deadly situations, but also from his unrelenting spirit.

Though he acts tough and battle-hardened, Sugimoto has a strong moral code, always striving to protect the innocent and honor his fallen comrades. His relationship with Asirpa softens his rough edges, revealing his sense of humor and appreciation for the Ainu culture. Unlike many who seek the Ainu gold for selfish reasons, Sugimoto’s motivation is personal and noble he simply wants to help Umeko and keep his promise to Toraji.

At times, he displays moments of recklessness and impulsiveness, particularly when fighting, but his tactical intelligence and quick thinking often help him survive even the direst situations.

• The Quest for the Ainu Gold
  Sugimoto enters Hokkaido as a simple prospector, but his life takes a drastic turn when he learns of the stolen Ainu gold and the mysterious tattoos that hold the key to finding it. His journey becomes intertwined with Asirpa, an Ainu girl seeking revenge for her father’s death, and together, they set out to uncover the secrets of the gold.

• Surviving Against Impossible Odds
  Throughout his adventure, Sugimoto faces ruthless hunters, soldiers, and criminals, each with their own stake in the gold hunt. Despite the dangers, he relies on his battlefield instincts, combat skills, and raw determination to survive. His “immortality” is repeatedly tested as he endures brutal fights, gunshot wounds, and near-death experiences, yet he always pushes forward.

• A Bond with Asirpa
  One of the most important relationships in the story is his partnership with Asirpa. While initially an unlikely duo, Sugimoto and Asirpa develop a deep familial bond, with Sugimoto becoming a protective older brother figure to her. He deeply respects her strength, intelligence, and cultural heritage, often learning about Ainu customs and survival techniques from her.

• Clashes with Tsurumi and Hijikata
  Sugimoto finds himself entangled in a dangerous battle between multiple factions, including Lieutenant Tsurumi’s 7th Division and Hijikata Toshizō’s group. Both sides seek the Ainu gold for different purposes, leading Sugimoto to navigate a complex web of alliances, betrayals, and conflicts.