Jiren was a child, he returned to his house and found that his parents were killed by a villain. He was saved by Gicchin, who would become his teacher and took him away to improve his strength. Later, with his allies, Kitchen's other students, they fought the villain, but most of his friends and even his teacher died. His remaining friends gave up hope on avenging their lost ones and moved on with their lives. From that point onward, Jiren was alone and trained so he could become stronger, as he no longer believed in trust, only in strength. To Jiren, strength is justice, as strength is absolute, qualities which attracted Vermoud to him. He lived in solitude until he met the Pride Troopers. In the manga, Jiren was encouraged to join the Pride Troopers by his master Gicchin, who lost his life to a monster some time afterwards. Having never received his master's approval, Jiren sought strength further on his own, never understanding that the goal of his master having him join the Pride Troopers was to teach him the value of teamwork. Despite this, Jiren worked hard as a Pride Trooper protecting the lives of all he could in his universe, never even killing the villains he fought.

Jiren's power would eventually grow to be greater than that of even a God of Destruction; however, he was not interested in becoming one and so his comrade Top was chosen to be the God of Destruction candidate for Universe 11 instead. Jiren's wish was to resurrect his former master and he wants to fulfill it, no matter the cost.

Jiren's very existence was considered a rumor in other universes; he is known as the only mortal that a God of Destruction cannot defeat.