"Tell me, how do you define love?" 

Jeon Jiyoon, on appearance looks tomboyish, but is actually quite girly on the inside. Because of this, guys always assumed that she never had a feminine side at all. 

When Kim Sunggyu, her ex classmate, approached her to form INFINITE co., a business managing company, she thought it would be a chance for her to help and to show of her skills. 

The two of them worked hard to build the company up, with their blood and sweat, INFINITE co. became one of the best business managing company in Korea and everyone began to go to them for help in business managing. 

In the process, Sunggyu began to fall in love with Jiyoon, proposed to becoming her boyfriend.

After 2 years later, the two of them broke up. Sunggyu found another girl, Soyu, leaving Jiyoon hurt and alone.

How will Jiyoon manage this? With the company she build up together with her ex, yet having to suffer and give up on her pride because of Sunggyu.

------