Kirby is a major character that appears in the Sonic For Hire series. He is seen as a somewhat insane person who has the knack for murder. So far he has killed a Roly-Poly, a Waddle Dee, Noddy, Mecha Hitler, Taizo Hori, the bar heater, The bandits, Princess Potato, the Sonic on Ice cast, and four Waddle Dee butlers.
He made his first appearence in Sonic For Hire: Kirby where Tails gives Sonic a job to help Kirby kill his enemies, however the people Kirby tells Sonic to kill were nice, happy and good people. When Sonic tried to leave Kirby threatned to suck him up and steal his powers so Sonic had to kill one of those residents.
Kirby didn't appear until Sonic For Hire: The Battle: Part 02, where he helped Sonic kill Mecha Hitler and Taizo Hori.
Kirby appered in Sonic For Hire: Tapper and burned Tapper down. Kirby also appered in Sonic For Hire: Casino Zone: Part Two to help Sonic (and ate Princess Potato and got gonerea in his mouth). In Sonic For Hire: It's On, Kirby joined the Sonic on Ice crew and ate the whole cast.
He reappeared in Sonic For Hire The New Kirby, where he's skinny, a famous Hollywood producer, and he's still a psychopath. Because in he's a producer and Sonic's friend he's making a movie for him about his life called Sonic: One Bad Character with Tails as Sonic's co-star. In Sonic For Hire: Mass Effect, to make Sonic noticable in public, he put Sonic on Entertainment Tonight.
In Sonic For Hire: Two Bad Characters, he and Sonic were at the restaurant, Tre Douche where he said that they need to bring back Earthworm Jim and Dr. Eggman and was excited when Sonic changed the movie name to Two Bad Characters, made Tails the main character, and wanted him to get top-billing. In Sonic For Hire: Movie Magic, he is shown to be playing Mario, (because Mario is dead) and he didn't care if his making movie had completely different elements then what he originaly planed.
He appeared in the season 4 finale Sonic For Hire: The Red Carpet. His catchphrase is "love it". It's unknown whether or not Kirby survived the explosion, but it is revealed in Sonic For Hire: Falco, where Fox Mccloud told sonic that he and Falco were at Earth and became huge movie stars, "with the help of this pink penis looking guy". It indicates he's still alive.
He recently appeared in the season 6 finale Sonic For Hire: Reset. While the gang runs back to Sonic's house, Kirby sees them past him, and glad to see them. They didn't reply to him, and Kirby says he's gonna kill them. He's also now morbidly obese.
Later in Season 7, Kirby only appeared in Kung Fu.