Ruri Aiba

She is the leader of the Aiba Foundation. She is the daughter of a billionare noble family who were killed by a Darkstone and therefore created the Aiba Foundation to combat against the Darkstones. She is a Lightstone that has the ability to turn a crystal into a Lightstone and insert it into Alma to control his true powers. She became chairman of Alma's school to keep in contact with Alma. She has a twin sister named Aoi who also survived the Darkstone aftermath, but was crystallized. Her whole foundation is occupied with all female maids.