In order to approach the mystery of the strange disease'acquired feminization'that a man transforms into a woman's body, we interviewed a former man who is said to have developed feminization. Since he was a man, he satisfied his desire for approval by making his face feminine with the function of a smartphone app and uploading it to SNS to get likes, and being told that he was "cuter than a woman". From the beginning, a male college student who is dangerous. In other words, there is a female fallen nature. I used to say, "I'm having sex with a man, I don't like it."