Ep. 10: Kiyono struggles with ill-fitting bras during a catalog shoot for her mother's business.
Aired on March 8, 2010

10
As the cultural festival nears, Kiyono takes a job as a catalog model for her mother's underwear company. She requests bras one size too large, causing none of the prepared garments to fit during the photo shoot. Distraught by the situation, Kiyono rejects Nayu's advice to wear junior bras, insisting on wearing underwear that appeals to men. In response, Nayu decides to redesign the underwear to resolve the fitting issues and support Kiyono through the crisis.
Episodes
- Ep. 6 · Nayu proposes bra assembly to maintain harmony within the Underwear Society group.
- Ep. 8 · The Underwear Society visits a seaside ryokan, leaving Komachi embarrassed after he wakes up in underwear.
- Ep. 9 · Yako’s awkward incident with Kota and Haruka’s confusion over her chest pain at the summer festival.
- Ep. 10 · Kiyono struggles with ill-fitting bras during a catalog shoot for her mother's business.
- Ep. 11 · Nayu delays Kyoto move news while clubs prepare festival costumes
- Ep. 12 · Nayu moves away, causing Haruka to quit the Underwear Society after Tamaki's apartment burns down.