In this current universe, everyone has their own soulmates. Once you turn one, you will have a string tied around your wrist where the colour is specific to your soulmate. As you grow older and closer to meeting your soulmate, the string will gradually become looser. And the moment meet your soulmate and both of you make eye contact, the string will drop and a tattoo of the excat date and time the both of you met will be tattooed on your wrist.  

Lee Hana was the last among her friends to meet her soulmate. With all her friends finding their soulmates, Hana was slowly losing hope that she would ever get to meet her soulmate. On the day she turned eighteen, it was when she first felt her braclet becoming looser. She had just turned 20, and is in collage, taking on a part time job at a cafe in hopes of meeting her soulmate there. 

Kim Dongyoung, or known as Doyoung by his friends, is a 21 year old collage student who comes rich family. He had a group of guy friends he is really close to and they call themselves NCT. Doyoung is the moodmaker of the group and is also very loud, but very smart as well. Unlike Hana, he did not lose hope in finding his soulmate as only the eldest Taeil in his group of friends had found his soulmate. However, Doyoung does not want to get together with his soulmate until the both of them fall truly in love with each other.