Togepi was found as a Pokémon egg by Ash in Grampa Canyon in Attack of the Prehistoric Pokémon. Ash, Misty, Brock, and Meowth fought over the egg and competed to determine who would be the eventual owner. When the egg hatched into Togepi, the first thing it saw was Misty, and it chose her as its Trainer, thinking that she was its mother.
Although Togepi appeared harmless, it sometimes used Metronome to get out of dangerous situations. The first time it happened was in Pikachu Re-Volts. Butch and Cassidy's Drowzee was using Metronome to attack Ash and his friends. Misty's Togepi began using it, causing an explosion that sent Butch and Cassidy flying. It happened again in In the Pink. A Rhyhorn was about to charge the group when Togepi used Metronome to use Teleport. It also used the move later in the episode to stop a Hyper Beam attack by a Nidoking by using Reflect.
Despite the fact that Misty knew Togepi could battle, she only used it one time to battle Ash. In The Totodile Duel, Ash was using his Pikachu to battle Misty for ownership of a Totodile. Misty used Togepi, because she knew Pikachu would never attack it, as Pikachu would often babysit it. Using Charm, she ended up defeating Pikachu.
As a Togepi, it was sometimes mischievous. Despite being a baby, it would often wander away from the group and get itself and Pikachu into dangerous situations, usually resulting in Pikachu getting hurt but Togepi walking away unharmed. It was also very friendly towards other Pokémon, particularly ones that were small, young, and/or wild. The most notable were a Voltorb in The Underground Round Up, a Sentret in Tanks a Lot!, and, much to Misty's dislike, a Caterpie in The Bug Stops Here.
In the Christmas specials, Togepi was seen Running away form pikachu and found the baby Kangaskhan back to its family. It was also seen making the Snorlax Snowman. it was also seen in the special episodes in Misty's arms.
As Ash, Brock, May, and Max met Misty near the gate to the Mirage Kingdom in The Princess and the Togepi, it was kidnapped again by Jessie, James, and Meowth, who were temporarily working for Colonel Hansen, a crooked Mirage Kingdom official. Colonel Hansen wanted to get his hands on Misty's Togepi so he could rule the Mirage Kingdom. Since Colonel Hansen is an impure-hearted person, his taking over the Mirage Kingdom would destroy the Togepi Paradise.
Togepi later evolved into a Togetic in A Togepi Mirage! in order to protect the other Togepi. When Togetic was injured by Colonel Hansen, Misty promptly sent out her Gyarados and defeated Hansen's Shedinja with a Flamethrower attack. After seeing the damage Hansen had done trying to reach the Mirage Kingdom, Misty respected her Togetic's decision to stay behind and released it, so it could protect the Kingdom, the Togepi Paradise, and the Togepi who lived there.
