The "Dragon Ball" manga series features an extensive cast of characters created by Akira Toriyama. The series takes place in a fictional universe, the same as Toriyama's previous series "Dr. Slump", and follows the adventures of Son Goku from his childhood through adulthood as he trains in martial arts and explores the world in search of the seven orbs known as the Dragon Balls that are used to summon a wish-granting dragon. During the course of the story, he encounters allies such as Bulma, Kuririn, and Trunks, rivals such as Tenshinhan, Piccolo, and Vegeta, and enemies such as Freeza, Cell, and Majin Boo. The manga's anime and film adaptations feature some original characters not created by Toriyama but by the animation staff. 

While many of the characters are humans with superhuman strength and/or supernatural abilities, the cast also includes anthropomorphic animals and extraterrestrial lifeforms. The series also includes depictions of the afterlife, where several characters are gods that govern the universe, and parallel universes as well. 

Akira Toriyama initially based most of the characters on those of the Chinese novel "Journey to the West", Goku being Sun Wukong, Bulma as Xuanzang, Oolong as Zhu Bajie and Yamcha being Sha Wujing, and redeveloped one of his earlier one-shot manga series, "Dragon Boy". To be creative with the character, Toriyama stated in 1995 that he designed Goku not as a monkey like the "Journey to the West" character, but as a human-looking boy with a monkey's tail to give him a distinguishing feature. However, in 2003 he elaborated saying he added the tail because his editor told him without it Goku had no distinguishing features, even though this was probably a joke, he went ahead and did it. Toriyama later stated that the tail was a pain to draw, hence why he had it get cut off early on, and that he never thought of making Goku an alien until Vegeta appeared.
Does it connect to another of the author's creations?
fictional universe, the same as Toriyama's previous series "Dr. Slump", 