"Sorry to your girlfriend, but... I'm going to borrow Jin-kun's help."
Jin, trying to impress the girl he liked, lied and said he had a girlfriend. Later, that very girl announced to Jin, "I got a boyfriend." While overwhelmed by disappointment, one day Jin was suddenly called out with, "I have something I want to discuss." The misunderstandings between the boy and girl eventually led to pure, passionate sex.