Split-Chinned Kid

The Ball-Chinned Kid is the grandson of Agoni, the multimillionaire founder of the Hero Association, best known for being saved by Saitama from Crablante three years before the series begins.

Mischievous by nature, the boy once drew crude marks on Crablante's body with a permanent marker while the monster slept in a park — the very prank that later put his own life in danger. He can also be somewhat oblivious to real stakes, fretting over a lost ball even while facing mortal peril. When Crablante finally caught up to seek revenge, Saitama stepped in without hesitation, saving the boy and cementing one of his earliest quiet heroics.