Kogasa Tatara is a tsukumogami transformed from an abandoned umbrella, a karakasa-obake (umbrella ghost) in Japanese. No matter how small, every tool has a god dwelling inside it, so you should always treat your tools with respect.

If a tool that has been used for a long time is disposed of without a proper memorial, the god dwelling inside it cannot regain their form. These imprisoned gods become tsukumogami. Some of them commit wrongdoings toward their previous owners.

Kogasa is good at looking after children. When she sees a crying child, she rushes to make them smile. When a child is laughing, she goes to surprise them. (She's a youkai―it's in her nature.) While adults cannot handle her, children absolutely love her eccentric-looking umbrella. (Kogasa is not too fond of it herself though.)

Kogasa spends most of her time at Myouren Temple, although she is not a disciple. She stays there simply because many humans visit the temple, which gives her a lot of targets to scare.

A memorial ritual for old sewing needles called Hari-Kuyou is held on February 8. On that day, Kogasa needs to find a new job or she will not be able to enjoy herself for a year. She once made new needles for Reimu and ended up being attacked with them because Reimu wanted to test them out. Of course, the needles passed Reimu's test with flying colors.