Keia, the main character of this story, was found in a stream as a newborn. Their town viewed them as a bad omen because of this (and because of their appearance), which led to repeated harassment, bullying, and alienation from the rest of the citizens. Keia grew up with a lot of resentment towards everyone who raised them except for their adoptive mother, Ariadne. Confused about their past and unsure of their identity, Keia joins an organization that promises answers after Ariadne's death -- only, this organization is one of the world's most notorious terrorist groups.

During the story, Keia is enlisted to assassinate Cassius, the son of a very powerful businessman with a strong political influence. Upon getting to know Cassius in order to get close enough to assassinate him, Keia discovers that the narrative the terrorist group has been telling them their entire life isn't entirely true, and they must choose between loyalty or true belonging.

Keia is very intelligent, independent, and good at making decisions, but as a result they act solely in their own interests and are not good at forming close relationships. They spend their free time travelling and studying humans, with which they share half of their blood.

PLEASE NOTE: Keia's design has changed a lot over the years. Therefore, they may look drastically different in some art.