Nayu's step-brother who has been looking after her since their parents died. He works as an underwear designer and often gets Nayu to test out his latest products.
Chu-Bra!!
The story centers on Nayu, a middle school girl who shocks her schoolmates on the first day of school by wearing black lace panties. She likes this kind of underwear, and she tries to "spread the word on the merits of [these kinds of] underwear" via an underwear club with her schoolmates, who are worried about their bodies' development and which underwear to choose.
