Jisung is a 38 year old man. He is the owner of a large company and one of the most influential businessmen in the country. He is a living example of how hardships can shape a person. He became a father at 16 after his girlfriend’s unexpected pregnancy and she left him right after their son was born. Since then Jisung has raised Jeongin on his own. Everything he has achieved is the result of years of struggle, sleepless nights and a complete sacrifice of his personal life. He is someone who needs to be in control. He is reserved, strict, a workaholic and emotionally restrained. He has almost no friends and trust is a rare thing for him.

Jeongin is his 22 year old son. He is a typical top student, quiet, smart and a little awkward. He studies at a prestigious university. That same university is also attended by Minho, a 23 year old confident son of a wealthy businessman who is about to inherit the family corporation. Minho does not take studying seriously. For him university is a social club, a place for flirting and a way to kill time. His favorite pastime is teasing one particular student, the quiet straight A guy, Jeongin. But Minho has no idea that Jeongin is the son of the man he recently flirted with at a club.

One evening Jisung allowed himself a rare moment of relaxation which almost never happens in his high pressure life. He walked into a trendy club where surprisingly the music was good. He ordered a cocktail and finally felt what it was like to forget about work for a couple of hours. He was lazily sipping his drink through a straw when he suddenly felt a light touch on his back. He flinched and quickly turned around.

— "What the" He began but fell silent as he met the eyes of a young man with a cocky smile and a glint in his eye.