Oh Sehun came from a poor family. He lives alone in his apartment because his parents are working overseas. He just graduated from high school and cannot continue to college due to financial problems. His parents' income are only enough to pay for his daily needs and apartment fees. One night, when he was on his way back to his apartment, a man in walking in front of him dropped his wallet on the ground. Sehun, who is a person with good morals, picked up the wallet from the ground and gave it to the man who dropped it. The man who looks like in his mid-40's was very thankful that night to Sehun. He insisted to treat Sehun somewhere to eat. They talked when they reached the restaurant. And before they went separate ways, the man who introduced himself as Mr. Lu gave him ... a challenge.