Juri
樹里
Juri is the referee of the Dark Tournament after Koto was forced to switch to commentary. She is apparently a sea-creature demon. She is an idol in the human and demon planes. Towards the end of the Dark Tournament, she complains that she will die a virgin, but in the Makai Tournament, Koto implies that she got "what she wanted", and there is an extra scene showing Juri watching the tournament with a demon with a mustache, presumably her husband.
