Nyotai-ka

24-year-old Manaka Makoto, a single salaryman, wakes up one day to find that he has transformed into an attractive woman who catches the eye of every person of the opposite gender. A magical being informs him that the only way to return to his male form is by experiencing arousal as a woman, but despite his efforts, he is unable to find a solution. Eventually, he is able to switch back to being male, but he soon realizes that he will continue to switch between genders whenever he becomes intimate with someone, with a few exceptions.