Also known as: ざんこ, 恐子
ARuKo's companion, often seen in art together. A young girl with long Blue Hair and Glasses, wearing a Domino Mask underneath them.
She may or may not be based on Da Vinci Osorezan (ダ・ヴィンチ・恐山), co-host of Tokumei Radio (匿名ラジオ) with ARuFa.