Aerith
Aerith Gainsborough is a character who lives in Traverse Town in Kingdom Hearts and Hollow Bastion/Radiant Garden in Kingdom Hearts II. She is from the Final Fantasy universe.
Kingdom Hearts
Aerith is encountered by Donald and Goofy on the first trip to Traverse Town, where she explains the nature of Ansem's Report, as well as the Keyblade to them.
Chain of Memories
An image of Aerith appears, along with Leon, Cid, and Yuffie, in the memory-based Traverse Town in Castle Oblivion. At first, she, like the other characters, expresses disbelief that she seems to know Sora despite not remembering him. After speaking with Sora, however, she comes to realize that she is just a projection based off his memory of her. She and Maleficent in Riku's game are the only ones to realize this.
Kingdom Hearts 2
Aerith is a member of the Hollow Bastion Restoration Commitee.