Kim Hee Sung is a normal 17 year old girl who works in a Bubble Tea shop called "Bubble Pop" together with her younger brother Kim Hee Seng. Bubble Pop was located a bit outside of Seoul so not many people came there often. But alot of the trainees from different companies usually visits during the night time. It was because most of their dorms were only a few minutes away if you take the train. Hee Sung is a very polite and kind girl so alot of the trainees liked her, she was really beautiful too, while Hee Seng is a very over protective little brother. He doesn't want him and his sister to be hurt again. 

What happens when new customers come to Bubble Pop? What will Hee Sung do when a few of them keep staring at her when she's just sitting there behind the counter? They become very close friends but when they start thinking about it.. Hee Sung knows almost everything about them, but they don't know anything about her? Will any of them get feelings for her?

What will happen when Hee Sung decides to quit working at Bubble Pop for no reason? Or is there a reason..?