Bubbles is a monkey, whom serves as both a pet as well as a friend to North Kai. When Goku first arrived to King Kai's planet he mistakenly mistook King Kai to be Bubbles. Although this was certainly not the case. As is turns out, after meeting King Kai, Bubbles plays an integral role in the beggining stages of Goku's training. Shortly after, King Kai instructs Goku to try and catch Bubbles. Although the task of catching a mere monkey on Earth would prove in itself to be a superfluous task, on King Kai's planet this was not the case. This is due to gravity of King Kai's planet, which is ten times stronger than that of Earth's, making it difficult for Goku to move his body quick enough to catch Bubbles, who after living on the planet for so long has adjusted to it. Bubbles is used once again after the death's of Piccolo, Yamcha, Tien and Chiaotzu in order to train. During the Perfect Cell Saga Bubbles is later killed when Cell self destructs on Kai Kai's planet.