Plot: Protag Aoi sees an interview of popular former "sexy actress" (AV actress) Asui Rin on TV, who looks young despite being middle-aged. He comments to himself about how her just being born a woman makes life so easy: become a celebrity after making a fortune selling her vag, then make even more money. If only he was born female, he could sell his body and escape from his home situation. His mother seems to be ill (profile page says he has no father) and they're on welfare payments.
Aoi goes to school, gets told by female teacher that the school is taking back recommending him for a good university, because another student wants to go to that uni, and because of Aoi's family being on welfare. She lectures him on how welfare payments are paid for by taxes from hard-working adults, such as teachers like herself, so Aoi should skip higher education, get a job and contribute to society. "WTF is this woman saying??" he thinks to himself. "Am I at fault? I just want to escape from this world already..."
On his way home, as he contemplates suicide, Asui Rin appears before him. "Then before you die, will you listen to my request?" Shocked that it's the actress herself, he says "Someone like you who abuses women's weapons for gains wouldn't understand my suffering!!" and Rin reveals that she was a man up until 4 years ago. She wore a magic ring that transformed her into a real woman, keeping her consciousness and memories, while the rest of the world believes she was always born female. Once you wear it, you can never become a man again. She has an extra ring and gives it to him, saying she has reasons for doing so, but can't say.
With nothing to lose, Aoi decides to try the ring. Wakes up next day as a girl, immediately hops onto dating site to sell her body and earn money to escape her home and town. Finds her teacher's bank staff fiance on the dating site and decides to seduce him to get revenge on her. Because she's a former guy, she knows how to act exactly how guys want, using women's weapons better than women. "So easy!!!! Aren't young cute girls too invincible!?"
Later, a video of the female teacher's fiance sleeping with a high schooler was uploaded to the internet, causing her to be depressed and quit school. Aoi gets the uni recommendation back. "In just one night, I messed up that shitty woman's life. With this body, it feels like I can do anything!!" When she gets home, there's another ring in her mailbox. To be continued...