Ji Na seems to have decided that this will be their last day together. They do fun couple things. At one point, while he meets a delivery person, she answers his phone for him. The city has fixed the traffic light near her place because Seung Min was calling several times a day, every day, to make sure they fixed it. Touched, she takes his picture when she sees him walking back towards her. At school, Han Na tells Tak to do his best to win Ji Na over so that she can have a chance with Seung Min. He asks her who she's trying to win, Seung Min or Ji Na, and she says both. He points out that Ji Na seems to be the only one who ever thought of them as friends then. At midnight of day 50, she leaves him, telling him that the contract is over and she won't be keeping him. She walks away in tears as he looks on, hurt and surprised. (Source: Dee at MyDramaList)