Mr. Popo is a deity in the Dragon Ball series. He is an immortal genie who tends the grounds of Kami's Lookout and is bound there eternally as the gardener and caretaker. He uses a magic carpet for Instant Transportation.
Though he may not appear to physically age, Mr. Popo is very old; having served Kami, the Guardian of Earth for hundreds of years, he also served Kami's predecessor, as well as every other guardian of the Earth in the past. Being the loyal and faithful servant that he is, his purpose consists mainly of tending to Kami’s Palace, keeping the Lookout clean, helping to reconstruct Shenron if needed, and most importantly, taking care of Kami. He also tends to the ancient butterfly garden that he planted thousands of years ago, and enjoys the more simple things in life. While Funimation’s English dubbed Mr. Popo speaks complete, highly sophisticated sentences, the Japanese version proves him to be a seemingly primitive figure. His grasp of the common tongue is less than the English-dubbed version makes it out to be, and in addition, the Japanese version has him commonly referring to himself in the third person, which is done in the English version too as well as in the video game Dragon BallZ: Budokai Tenkaichi and in the manga.
Although his skill as a martial artist is not shown frequently, Mr. Popo is an excellent martial arts master. When he is introduced in Dragon Ball, he is far stronger than Goku when the two meet at the Lookout. He trains Goku for three years until the young warrior learns everything he knows, and enters the 23rd World Martial Arts Tournament to defeat Piccolo Jr. with his newly attained abilities. Some of the techniques Goku developed in his three-year training later proved valuable; such as the Super Kamehameha, a more lethal version of the trademark attack. When used against Piccolo Jr. in the World Martial Arts Tournament, however, the demon survives it with minimal damage.
In the filler Garlic Jr. saga Mr. Popo is attacked by Garlic Jr.'s henchmen while watering the plants on the Lookout. He is sealed in a glass cup by Garlic Jr. Later, he is released by Krillin and Piccolo. He takes Kami to the bottom of the Lookout to spread the Sacred Water where the former Guardians' graves lie. He later spreads the Sacred Water to the Earth.
The Androids and Cell
Mr. Popo plays a fairly small role during the Cell arc. He leads Goku, Gohan, Vegeta, and Trunks to the Hyperbolic time chamber and watches the fight with Cell at the Cell games
Seven years later, Mr. Popo comes up with the idea of having Trunks and Goten do the Fusion Dance after everyone else runs out of other ideas. The family and friends of the Z Fighters take refuge from Majin Buu on Kami's Lookout. Mr. Popo also observes the fusion of Trunks and Goten. A day later, Buu finds the Lookout and allows them to live for a short time. While there, Super Buu used his Human Extinction Attack to kill all the people on Earth, except for Mr. Satan, his dog Bee, and the family and friends on the Lookout. When Buu escapes from the Hyperbolic Time Chamber, Mr. Popo and the rest are turned into chocolate and eaten. Popo is later revived and gives his energy to help Goku make the Spirit Bomb to destroy Kid Buu.
Mr. Popo has a very small role in GT. He serves as a backround character mostly.