Aku

Aku is Ayis' soul split. This half was sealed in the tome for longer than his other half, Hikari.

Aku is very quiet and reserved, only talking to Klug exclusively.
He has severe social anxiety, regardless of wanting to interact with others greatly.
The anxiety comes from the fact that hes a half demon and how people will react to it.

He prefers not to speak to Hikari and generally hates his lifestyle and choices to converse with Amitie and other magic users.