Jongin was a child who had to stay in a sterile tent. Kyungsoo goes back to the seaside town where he used to spend his summer holidays as a teenager to get a rest from his work as a webtoon artist, and reminisce about his long-gone first love, Jongin. However, as he notices that he is being followed by footprints on the sand that belong to no one, he begins to feel like maybe the boy has never left this town.