The only human in the illusionary world, a world Tomoya dreams of. She creates a body out of garbage for an unnamed entity only referred to as, "Me," so that she will not be alone in the illusionary world. She is not created by CGI, everything she does is hand-drawn. (Source: Wikipedia) After Story

Spoiler

It is revealed that the girl is Ushio, Tomoya's daughter in a world with her father after she dies in the real world.