The romance between top star Hoo Joon and his anti-fan reporter Lee Geun-young who end up living together.

Lee Jae-in (Ha Seok-jin), a ruthless son from a wealthy family starts seeing an elementary school teacher, Kim Da-hyun (Jeon So-min) whom he has never seen before, on a six-month contract engagement, so that he could inherit the asset as written on his grandfather’s will. '1% of Anything' is a romance drama depicting what happens to the pair during the fake engagement.

The story is about a boy, Lee Sin, who is popular in his High school for his band team- "The Stupid", and a girl, Lee Gyo Won, from the same institution, who is devoted to traditional Korean music. Lee Sin's father, Lee Hyun Soo was a popular guitarist during his time but is now in the verge of death because of drug addiction; which was also the cause of his separation with Song Ji Yeong (Lee Sin's mother) a long time ago. The female lead, Lee Gyo Won's grandfather, Lee Dong-jin is one of the top 3 traditional musicians of his age and his biggest wish is to see his granddaughter become a traditional music prodigy. He is strictly against modern music because he believes that it misleads the tradition. The high school comes up with "The 100th Year Anniversary" where students get the opportunity to show their skill. Now, will Lee Sin be able to prove his skill in modern music like his father did? And will Lee Gyo Won be able to keep up her grandfather's expectations? Or something else is...