Park Yoon Jae is a university student studying astronomy. He met Kim Ji Eun on his first blind date while attending university. They fell in love and became boyfriend and girlfriend. One day, a strange man appears in front of Yoon Jae and tells him that he is Ji Eun. Ji Eun is pretty and a warm-hearted woman. One day, she wakes up and finds herself changed to a man. She explains the situation to her boyfriend Park Yoon Jae. She begins to use the name Kim Ji Hoon and learns how to live as a man from Yoon Jae. The two decide to not break up and to wait for her to return to her original female appearance to continue their relationship. They try to figure out a way to make that happen. Meanwhile, popular girl Kang Min Joo attending the same university as Yoon Jae has a crush on him. (Source: AsianWiki; edited by MyDramaList) Adapted from the webtoon "My Girlfriend Is a Real Man" (내 여자친구는 상남자) by Massstar (맛스타).