One of the things Yvon hides in his house. White hair, grey eyes, a discarded subject from the birdcage because she can't speak, write, taste, smell and is a general failure of a human being. She can sense the future and other things, however (it's how he found out her power, because she can predict his moves when they played games of chess). On her birdcage file the name was "Hyrea", but in the house they call her Tsukiyomi or just Tsuki-chan.