Koshiba Mao, a plain-looking office worker, finds out that her boyfriend, with whom she was in an office romance, is cheating on her. The next morning, desperate and drowning in alcohol, she wakes up in the bed of a handsome stranger! The handsome man, Ando Hajime, appears as her new boss at work and tells her a shocking truth... “You are no longer Koshiba Mao, you are Ando Mao." To her surprise, Mao had gotten married in a drunken stupor! Mao's life, which was supposed to be ordinary, is disturbed by Hajime, who somehow becomes infatuated with Mao, whom he just met. Around them there are Mika, a condescending woman who is after Hajime, and Kota, a morally harassive man who cheated on Mao with Mika. This is a deep adult love story that reveals the reason why Hajime loves Mao and the hidden truths of the characters one after another!
