Short answers, pulled from the story.
Birdie first appeared in the original Street Fighter game released in 1987 as a non-playable opponent. He stood among multiple enemies that Ryu or Ken Masters had to defeat during their journey.
Artist Naoto Kuroshima, known by the nickname Bengus, handled his redesign for that new entry. Development teams changed his ethnicity to black as development progressed through the early 1990s after originally depicting him with light skin.
Director Takayuki Nakayama wanted to include Birdie to add a comedic element to the roster. He drew inspiration from the character's previously displayed large appetite and low work ethic before settling on a fat version.
He utilizes a chain-based fighting style driven by gluttony rather than direct aggression. The chain allows him to grab and throw opponents with unique animations while focusing on manipulating the opponent's movement more than his own actions.
Wired writer De'Angelo Epps called Birdie the epitome of a Black caricature in video games. ComicsAlliance writers Chris Sims and David Uzumeri questioned if Dudley's inclusion responded to player reactions against Birdie and described him as quite possibly the most racist video game character ever created.