Kiri Komori is a student who appears in the anime Zoku Sayonara Zetsubou-sensei. She is a member of the problematic class 2-F, where she is known as student number twenty. Her name is a direct wordplay on her defining characteristic; in the traditional Japanese order, her name evokes the term komorikiri, which means staying at home, and when rearranged, it sounds similar to hikikomori, the term for a person who becomes a recluse by withdrawing from social life.

Kiri is a hikikomori, or a shut-in, who had completely withdrawn from the world and refused to leave her home. Her teacher, Nozomu Itoshiki, was asked by a colleague to visit her in an attempt to bring her back to school. This intervention led to a compromise; while she agreed to leave her house, she was not ready to fully integrate into a normal school environment. Instead, Kiri took up residence in an unused classroom at the school, effectively becoming a shut-in within the school grounds. This unique solution allows her to be present at school on her own terms.

In terms of appearance, Kiri has long, dark hair that reaches her waist and brown eyes. She is almost never seen without her favorite blanket, which she wraps around herself constantly. The blanket acts as a portable sanctuary, creating a small, enclosed personal space wherever she goes. The clothes she wears underneath this covering are variable, sometimes simply her underwear, as the primary function of the blanket is to provide a sense of security and isolation rather than warmth or modesty.

Kiri's personality is defined by her profound shyness and quiet nature, stemming from her extreme agoraphobia and aversion to open spaces. Unlike a stereotypical hikikomori who might fear all social interaction, Kiri is capable of interacting happily with a select few individuals she trusts. She is very sweet and gentle when talking to Nozomu Itoshiki. Furthermore, she takes on a caring role with Majiru, Nozomu's young nephew, acting as a protective and nurturing figure for him. Kiri's primary motivation appears to be the maintenance of her safe, enclosed environment. She seeks out small, random enclosed spaces throughout the school to hide in, often carrying her blanket with her to transform any location into a suitable refuge.

Within the story's ensemble, Kiri's most significant relationships are marked by both affection and rivalry. She holds a clear affection for her teacher, Nozomu, which becomes a point of jealousy. She becomes annoyed whenever another student, particularly the serial stalker Matoi Tsunetsuki, shows interest in Nozomu or tries to claim him. This tension is described as leading to off-air battles between Kiri and Matoi, suggesting a comedic, unspoken competition for the teacher's attention. Kiri also has a notable connection to Majiru, Nozomu's nephew; during events occurring outside, such as an alien invasion, Kiri is depicted spending time with and looking after Majiru inside.

Kiri shows a subtle but important development in her character. While her core desire for seclusion remains, she progresses from being completely confined to her family home to finding a way to exist within the school environment. Furthermore, her relationship with Majiru reveals a capacity for responsibility and care that extends beyond her own needs for isolation. She demonstrates a notable ability to move between her designated classroom hideout and various other enclosed spaces, such as Nozomu's house, using her blanket as a constant companion and shield against the outside world. This ability suggests a strong, if unusual, willpower when it comes to following her attachments, even if it means briefly confronting the open spaces she so dislikes.