Jaco

Jaco's backstory is revealed in his own spin-off manga, which takes place years before the main Dragon Ball story. He is sent to Earth on a mission to intercept and neutralize an alien baby being sent to the planet, a baby who turns out to be the infant Goku. Jaco fails spectacularly at this assignment, spending most of his time on Earth eating, bumbling through social situations, and befriending an old man on an island who turns out to be connected to Bulma's family through Dr. Brief.

Despite his failures, Jaco's heart is generally in the right place. He genuinely wants to protect the innocent and uphold galactic law; he simply lacks the competence to do so effectively. His tendency to panic in combat situations and his inflated opinion of his own abilities create a constant gap between his self-image and reality that drives much of the comedy surrounding his character.

In Dragon Ball Super, Jaco arrives on Earth to warn the Z Fighters about Frieza's impending return. He participates in the battle against Frieza's army during the Golden Frieza Saga, though his combat contributions are modest at best. His presence serves more as a narrative bridge between the Galactic Patrol organization and the Earth-based fighters.

Jaco's most significant contribution is connecting the Z Fighters to the broader Galactic Patrol, which becomes important during the Galactic Patrol Prisoner Saga when the ancient sorcerer Moro escapes from galactic prison. Through Jaco, the heroes learn about threats that exist beyond Earth and become temporarily deputized as Galactic Patrolmen themselves.

As a character, Jaco represents Toriyama's love of gag manga and absurdist humor. He is a deliberate contrast to the ultra-powerful warriors that dominate Dragon Ball, serving as a reminder that the universe is full of ordinary people (and aliens) trying to do their jobs. His self-awarded title of "super elite" and his constant need to remind everyone of it make him one of the franchise's most endearingly delusional characters.