Junjou Gal wa Kanojo ja Nai noni

On an ordinary morning, Hirakawa Asahi, an average high school boy, turns on the TV in the living room as usual. The news program began with a report on hot springs, and that's how my otherwise uneventful day started. Until the topless female reporter appeared on screen... Asahi is confused but tries to adapt when she realizes that the concepts of chastity for men and women are reversed. Meanwhile, Riria Sotogahama, a popular girl in the same class, confides in him that she has no experience with men.
Source: MU