Demi is an ancient android who takes care of Motavia's enviromental computers. She was kidnapped by Zio and rescued by Chaz and company, joining them shortly thereafter. She is wise and collected, having a broad range of knowledge of the Algol system.

As a dueller, she is defined by her durability. Having high defenses with plentiful healing and being able to buff her magical defense (along with halving Fire and Ice attacks), she is hard to take down. Her Phononmeizer skill is also a reliable source of damage. Unfortunately, being an android, she suffers strongly when hit by Lightning.