Machi is a character from the anime Nagasarete Airantou. She is the older sister of Ayane, though she appears smaller and younger-looking than her sibling, and is actually eighteen years old. Despite her innocent appearance, Machi possesses a sadistic streak and delights in causing others discomfort, particularly her younger sister. She owns a voodoo doll that she uses to inflict pain on Ayane, deriving pleasure from the frightened and pained expressions she elicits. This tendency carries over into her general approach to tasks: whenever Machi needs to accomplish something, she habitually chooses the most dangerous or indirect method available. She is also a master schemer, often devising plans that succeed as long as they are not thwarted by Ikuto or an adult figure.

Machi has a notable weakness regarding her age. She is extremely sensitive about being considered old, and any remark about her age causes her visible shock and distress. This sensitivity fuels her primary motivation in the story: she believes she should be married soon, and as a result she develops a romantic interest in Ikuto, the only young man on the island. Her pursuit of him is driven largely by this anxiety about her age and the desire to secure a husband before it is too late.

In the context of the series, Machi serves as a supporting character who adds comic relief through her cruel pranks, her obsession with marriage, and her dramatic reactions to being called old. Her key relationship is with her sister Ayane, whom she frequently targets with her voodoo doll. She also interacts regularly with Ikuto, viewing him as a potential marriage partner. Beyond her voodoo doll and her talent for manipulation, she does not display any overt supernatural or combat abilities; her primary skill lies in psychological torment and elaborate scheming. Throughout the series, her character does not undergo major development, but her fixation on marrying Ikuto and her sensitivity about aging remain consistent traits.