The character Goku is based on Sun Wukong, the central character of the Chinese novel "Journey to the West". To be creative with the idea of Sun Wukong, Toriyama designed Goku as a human boy with a monkey's tail, rather than a complete simian, because the tail would give the character a distinguishing feature. He later stated that the tail was a pain to draw, hence why he had it get cut off early on. Toriyama did not initially plan to make Goku an alien, it was not until the introduction of fighters from other planets that he established him as a Saiyan. Goku was given the ability to teleport to any planet in seconds, so that Toriyama could increase the pace of the story.