It is required that all high school students do at least 40 hours of community services before they can graduate. Some find this task a drag ; some find it a great opportunity to hang out with friends. 18 year-old Yoon Rihae thinks neither. She thinks it's a perfect chance to truly help the community, so she voluteers at the hospital weekly. Of course, as a teenager she goes out with her friends quite often. One night they go to a outdoor fesitval where fun and excitement lies in each tent. Vendors are busy selling, cusotmers are busy eating, volunteers are hoping the night would end. A booth catches Rihae's attention - One match. It was a booth where people would be swabbed from the inside of their cheeks to see if they would match a patient's. If it did, they would undergo a procedure where they would take some cells and blood,  to cure them of their disease. Rihae and her friends have been asked many times to donate-but they were too young. This year, she finds herself donating blood to a total stranger. She wonders who he/she is.

Meanwhile, 20 year-old Byun Baekhyun has been sitting on the hospital bed for the last 3 months. His dream of being a celebrity was crushed when leukemia striked the boy just before his debut as "EXO".  All his friends were tested to see if they could save him and his dreams. Sadly, their blood and cells just werent meant for him and they were forced to debut without him. Spending his days in the hospital, Baekhyun is lonely and is hoping to find some company. But what he wants more than company, is to accomplish his dream.