Mai (pronounced "May") is a teenage girl who lived in the Fire Nation until her father was appointed by Fire Lord Ozai to be Governor of the Earth Kingdom city of Omashu. She had been living in Omashu with her family ever since, until Princess Azula showed up. Azula was forming a small elite team to hunt down Zuko and Iroh, and she wanted Mai to be a part of it. Mai instantly agreed, partially because she hated being in Omashu.
Mai is very unemotional (even when a family member is in danger), and finds almost everything dull and boring. She enjoys fighting though, and is quite skilled at throwing blades. She also has a small, machine-like weapon holder strapped around each of her wrists and ankles that shoots small arrows.
Mai is a childhood friend of Azula and Ty Lee, and they attended the Royal Fire Nation Academy for Girls together. She's had a slight crush on Zuko since she was little, which Ty Lee and Azula are aware of, and have occasionally teased her about it (both when they were little and older).