Shoken Chin

Shoken is the son of Master Chin, and prior to the events of "Goku vs. Sky Dragon," the only remaining member of the Chin-Star School.

Biography
Shoken is first seen running from Rising Dragon because Dragon believes that Shoken had stolen his wallet. After Goku stands up to Rising Dragon, he asks Master Chin for a sparring session, to which Shoken interrupts, telling Chin not to waste his time with an "amateur" like Goku. Chin spars with Goku anyway and as a result, is overwhelmed by his sickness. Shoken blames Goku for this and sends him to pick up some medicine for Chin. Later in the Chin-Star dojo, Chin explains to Shoken that he would not be able to compete in King Wonton's Royal Match against Sky Dragon.

Shoken insists that he should stand in for his father, but Chin knows better than to pit his son against Sky Dragon. Chin instead picks Goku. This enrages Shoken because his father picked a stranger over his own son. Shoken then goes to fix up some breakfast, saying "At least I have enough skill to do that!" Shoken slips a laxative into Goku's food to try and stop him from winning the fight. By the time he realizes his mistake, the match is already underway. Goku wins the match and remains non the wiser about Shoken spiking his food. Shoken apologizes nevertheless.

(Source: Dragon Ball Wikia)