The former STU48 idol Yuka (sometimes Yuuka) Oki shows off her naked butt in her second photo book, which came out February 26 from Kadokawa. Swimming Allowed is the latest release from this slinky idol and features her in sensual lingerie and several shots in a milky bath. The best shot of all features her on her front in the bath, with her cute little butt poking up through the water. Another shot features the idol naked under a sheer dress. We think this is the most 25-year-old Oki has ever shown in a gravure shoot. To promote the book, she also appeared in a recent issue ...

Yuka Oki has just graduated STU48, the Setouchi-based version of AKB48, and seems determined to make a name for herself. And as past members of the AKB and Nogizaka sister groups have demonstrated (most recently Miku Tanaka and Ruka Kitano), stripping off is a surefire way to get attention. She hasn't done quite that, but Oki has done probably her sexist shoot yet. Aptly titled "Breaking Compliance," Oki's shoot for Flash sees her switch from music idol to gravure idol with aplomb, wearing a figure-hugging leotard or swimsuit that buttons up along the middle. The high-cut item really ...