A beautiful, fair-skinned girl whose looks are hidden behind her long hair and the blanket she wears most of the time. She is a hikikomori, but Kafuka believes her to be a zashiki-warashi. Nozomu and Kafuka unintentionally frighten her out of her home during an attempt to persuade her to resume attending her classes, and she now takes up permanent residence in school. She also falls for Nozumu when he was judging her as a good double suicide partner. She spends most of her time in an unused room, but turns up every now and then in odd places such as school lockers or toilet cubicles. Her name is derived from komorikiri, which means "always stays indoors".