A man full of mysteries, he leaves an impression of being coldhearted. When he suddenly appears, sometimes he offers advice, while other times he is antagonistic.

He is Yurika's older brother and his real full name is "有栖 椋士 (Arisu Ryoushi)"./

Translation of his URL=primula.jpn.com↗（新しいウィンドウで開きます） website profile.