King

is a giant gorilla that lives on the island Killer B and A train at. B calls him, as a sign of affection.

Appearance
King, like most inhabitants of the island is very large in size towering over the humans there. He is brown in colour with lighter shades of brown fur on his hands, face and chest. He also has green eyes and a prominent scars running down the left side of his body: above his eye, his mouth and along his torso.

Confining the Jinchūriki Arc
King appeared before the Kumo and Konoha ninja when Motoi guides them through the island. As King was about to attack them, Killer B calms him down telling him they're with him and they greet each other by bumping fists. King is later seen with Kintoki and the other bears, watching with interest as Guy opened his Eight Gates.

Trivia

 * King as well as his name is likely based on King Kong.