Mametchi is a character from Tamagotchi, a chain of egg-shaped virtual pet toys produced by Bandai that have since established a franchise spanning over 20 years, including adaptations to other media such as video games, merchandise, and anime. On most Tamagotchi releases, Mametchi is the result of a Tamagotchi with the best possible care, and has been portrayed as a well-mannered and intelligent Tamagotchi with an IQ of 250. Mametchi was initially one of several faces, but gradually became the mascot of the Tamagotchi franchise.
Mametchi's first (and currently only) appearance in the Mario franchise is in Mario Kart Arcade GP 2, where he is a playable guest driver presumably added to coincide with Bandai's then-recent merger with Namco. He is categorized as an Easy Control driver, sharing stats with Ms. Pac-Man and Toad. His special items are Bagubagutchi, Mame Block, Chibi Syrup, Mame Drink, and Giant Pencil, and his voice clips imitate the beeping sound effect heard in Tamagotchi virtual pets.
As with the other drivers, in addition to a standard kart, Mametchi gets a unique vehicle that slightly reduces acceleration in exchange for increased speed. Mametchi's unique vehicle loosely resembles a Tamagotchi virtual pet that is pulled by a wheeled mechanical Tamagotchi wearing a Kasa.