Sha Gojyo is a hanyou, the socially stigmatized "child of taboo" born to a human mother and a youkai father, marked by distinctive red hair and scarlet eyes. His early life involved severe abuse from his youkai stepmother, who directed her resentment over her husband's infidelity onto him. This abuse culminated in a violent attack where she scarred his left cheek and attempted to strangle him; his half-brother, Sha Jien, killed her in his defense. After this trauma, Jien abandoned him, forcing Gojyo to navigate life alone from age twelve.

Adolescence found Gojyo surviving through gambling and petty theft, often alongside a youkai named Banri who taught him street skills. He developed a reputation as a womanizer and heavy drinker, using these vices to cope with loneliness and societal rejection. His life shifted dramatically upon discovering the gravely injured Cho Gonou (later known as Cho Hakkai) on a roadside. Gojyo nursed him back to health, forging a deep bond. When Genjo Sanzo arrived to arrest Gonou for massacring one thousand youkai, Gojyo lied to protect him, triggering a confrontation. Gonou ultimately sacrificed his right eye to atone for his crimes before being reborn as "Cho Hakkai" under Sanzo's tacit forgiveness. Gojyo mourned Gonou's symbolic death by cutting his hair, later reuniting with Hakkai to solidify their lifelong friendship.

During the three years before their journey west depicted in the "Burial" arc, Gojyo and Hakkai lived together. Gojyo provided Hakkai with emotional stability as Hakkai grappled with his youkai transformation and past trauma. Their domestic life involved mundane routines, with Gojyo often indulging in habits like smoking and drinking beer. His weapon, a shakujou (a crescent-bladed staff), was acquired accidentally when he and Son Goku broke sealed urns containing sacred artifacts, resulting in the weapon bonding to him.

Personality-wise, Gojyo employs humor, flirtation, and provocation as defenses against his traumatic past. He frequently clashes with Goku in childish arguments and irritates Sanzo with his irreverence, yet demonstrates fierce loyalty to his companions. He shows particular protectiveness towards children and vulnerable women, reflecting his own experiences of abuse. Despite his lecherous facade, he expresses a longing for genuine love and connection. His resilience is underscored by the recurring motif that "there are other things in the world that are red" – a metaphor for finding hope beyond his blood-stained heritage.

As a hanyou, Gojyo possesses enhanced strength, endurance, and agility, though he lacks the elemental powers of full youkai. His combat style blends staff techniques with street brawling, emphasizing tenacity over finesse. The emotional core of his character revolves around his found family within the Sanzo party, where he evolves from a solitary outcast into a pivotal member who values camaraderie and sacrifice.