In Greek mythology, Maia is the daughter of Atlas and Pleione and the patron goddess of Nursing mothers. She is the eldest, shyest and most beautiful of the Pleiades, the seven sisters. Her beauty attracted Zeus who bred with her and so she gave birth to Hermes.
"From Greek mythology, the oldest of the Pleiades, the seven sisters who support the heavens. Incidentally, she is not a goddess, but a nymph. She had an affair with the chief god Zeus and gave birth to the god Hermes. Maia's name holds the meaning of "Grandmother of Magic" and is said to be the Western equivalent to Buddha's mother Maya, who is said to have created the universe."
Maia is the initial Persona of Maya Amano. As a child, Maya was able to conjure her Persona, whom she believed to be a guardian angel. Years later when she and the other main characters are attacked by a group of monsters, she summons her Persona again to protect themselves and learns the ability to invoke her Persona at will ever since. Maia's appearance is overall pink, red and black. Her clothes seems to be a combination of Japanese traditional clothing and the Gothic style. During the arson attack 10 years ago, Maia was able to break her host out of the shrine before the flames consumed her.
Maia returns as Maya Amano's initial Persona. Following the events of Innocent Sin, Maya has completely forgotten her memories, but she is able to summon her Persona once more when she is attacked by JOKER. Maia's appearance is somewhat changed. Her stats and battle skills remain almost the same, but now excels at the water element instead of the ice element. In Eternal Punishment's universe, Maya was never caught in the arson attack, and so never summoned her Persona until the JOKER attacked her.
In Persona 2: Innocent Sin, Reverse Maia shares the same base sprite sheet as Maia Prime with a different palette instead of the initial Maia.
Aside from the fact that Maia is used by Maya, her oriental design references the interpretation that the Atlas' seven daughters, the Pleiades, derive the Chinese Jade Emperor's seven nymphs, Tensen Nyannyans. Both are related to constellations (though the stars they represent differ) and have their youngest daughters, namely Merope and Zhinü, romantically involved with mortal males.
Maia's mythological connection to Hermes parallels the relationship between Maya and Jun Kurosu. Where Maya and Jun were mother and son figuratively in childhood, Maia and Hermes were literally mother and son in lore.
Maia and Maia Prime are the only Initial and Prime Personas who are not exclusive to one character, as Yukino can use them.