Ungaikyo

Birthday: September 13 Height: 273 cm Weight: 210 kg Also known as "the purple mirror". A yokai that resembles a huge flaming skull attached to a tiny lion-like body. It rides a bicycle and is able to travel via mirrors, trapping its victims in the same manner. If you look into its mirror, you will be killed on your thirteenth birthday.

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Kana first encountered it when she was 6 years old, when she and some other children found and looked into a purple mirror. The rest of the children turned up missing (and eventually dead) after they started middle school. It reappears on Kana's thirteenth birthday with the intent to kill her but is stopped by "Night" Rikuo.

(Source: Wikipedia)