Jiang Fujiu (RAIN) is a boxer with an extremely contradictory and autistic personality. His domineering aura is mixed with indifference and unruliness. Beside Fujiu, there is a girl named Han Dajing (Kim Sharon) who has spent her youth to protect him for ten years. Dajing once saved Fujiu but left a serious scar, so Fujiu is willing to repay her with his whole life. But in Fujiu's heart, there is another man he cares about the most, that is his brother Jiang Minjiu. Fujiu finally reunited with his brother who had been separated for 10 years, but before he could fully enjoy the joy of family reunion, he watched his brother jump from a tall building and become a vegetable. Fujiu deliberately looked for an opportunity to approach his brother's ex-girlfriend Che Eun-hee (Shin Min-a), who he believed was the direct murderer of his brother, and became her personal close follower, but in the two people's daily interactions, he fell in love with this girl who was actually simple and kind. Love should be a simple, pure beauty belonging to two people, but in this drama it is mixed with too many entanglements, the choice between family and love, the intersection of responsibility and true love... In the end, facing this damn love, where should the protagonist go.