English Premier League team Greenford’s ace, world star, the star of Asian football, and the ace and troublemaker of the South Korean national football team, Kim Mugyeom.

Wanting to repay the middle school coach who set him on the path of football, he willingly endures public criticism and even forfeits his salary to join K League team City Seoul on a one-year loan. There, he meets Lee Hajun, a rookie physical coach of the same age.

They had supposedly played in a World Cup together and had been called up for the national team multiple times, yet for some reason, Hajun had never left a strong impression to him. Even at City Seoul, he seems strangely intent on avoiding Mugyeom. "A rookie coach dares to avoid me, Kim Mugyeom?"
But it doesn’t take long for Mu-gyeom to pick up on Hajun’s peculiar behavior, “No wonder… He was way too quiet for a defender.”