Zhu Bajie journeys with Tang Sanzang's pilgrimage to India, seeking Buddhist scriptures as a disciple to atone for past sins. His divine origin lies in his former role as Marshal Tianpeng, commander of heaven's naval forces. Banishment followed his drunken attempt to seduce the moon goddess Chang'e during a heavenly banquet. A reincarnation mishap resulted in his rebirth from a pig's womb, leaving him a half-human, half-pig being.

His core personality showcases extreme gluttony, profound laziness, and relentless lust. He persistently pursues romantic or sexual encounters, often creating complications for the pilgrimage. Despite these flaws, he respects senior disciples like Sun Wukong, whom he calls "Big Bro," and maintains optimism in peril, trusting divine aid or his companions. His soft-hearted nature surfaces as compassion for women and children, sometimes urging mercy towards disguised demons exploiting this trait.

In battle, he brandishes the nine-toothed iron rake, a divine weapon forged for celestial war. His fighting style commands fire manipulation, conjuring potent fireballs and flames. Immense strength and durability enable him to confront multiple foes simultaneously.

No significant evolution occurs across his appearances. His consistent role provides comic relief through indulgences and failed romantic pursuits, though he occasionally aids the group's objectives through combat or problem-solving. Relationships involve frequent teasing from Sun Wukong and Sha Wujing about his appearance and habits, countered by mutual loyalty in conflict. His devotion to Tang Sanzang shows in respectful address and protective instincts when threats emerge.