Kazooie is a anthromorphic Red-Crested Breegull who is one of two main characters in the Banjo-Kazooie series. She is a red-crested breegull who lives in her friend Banjo's backpack most of the time, occasionally leaving it, to, most of the time, insult other characters. This attitude is the exact opposite of Banjo's.
Kazooie's name, like Banjo's, is based on a musical instrument: the kazoo. Incidentally, Kazooie herself is known to be an experienced kazoo player, although the only time Kazooie was ever seen playing her kazoo was during the introduction theme in Banjo-Kazooie. Oddly enough, Kazooie's kazoo barely resembles an actual kazoo and looks more like a bugle.
In 2019, she and Banjo were announced to be DLC fighters in Super Smash Bros. Ultimate.