Character: kirby
Kirby (JP: カービィ (Kaabii)) is the titular pink puff and main protagonist of Nintendo's Kirby series of video games named after them. The character was originally named Popopo (Along with the first game being named Twinkle Popo, which then later turned into Kirby's Dreamland and resulted in the today Kirby series. The original name is said to presumably match with Dedede, Lololo and Lalala) until Nintendo decided to name it its current name in honor of the american attorney John Kirby.
The series has been running since 1992, and nearly thirty titles have been released under Kirby's name, most of which are developed by HAL Laboratory, Inc. or published by HAL for co-developing studios.
Kirby lives in their dome-shaped home in Dream Land, a country on their home planet Planet Popstar. Their adventures take them throughout Dream Land and occasionally into local star systems for various reasons, and they have saved their homeland many times.
Kirby, despite being refered as male in localizations, was always gender neutral in Japan. It goes from having their gender stated as "unknown" in official books to Makiko Ohmoto (voice actress of Kirby) outright confirming it. (Hence why the official twitter account has Kirby to take roles of both men and women, most notably on Valentine's and White days). This makes tags like crossgender unapplicable to them.
Anime
Kirby is depicted as an infant Star Warrior who was called upon before their appointed time to protect Dream Land from the demon beasts sent by King Dedede using Nightmare Enterprises' monster delivery system. They are looked after by Tiff and Tuff and is only capable of only shouting the word 'poyo' repeatedly, with the exception of a few words (in the Japanese original). As the story progresses, they become more adept at using their powers and is eventually able to take on Nightmare by theirself on the final episode.
Manga
Kirby has various manga by various mangaka, with different characterizations. Most of them are only released in Japan with the exception of select pages from Hirokazu Hikawa's manga, which are localized in English as Kirby Manga Mania.
See also
This tag implicates kirby_(series) (learn more).