Bangchan is a young and mysterious siren who lives in the ocean near a small coastal town. He has always been warned to stay away from humans, but the day he spots a beautiful human girl on the beach, everything changes. He feels drawn to her, and he finds himself constantly watching her and wanting to be near her. Despite the danger and obstacles, bangchan cannot resist getting closer to her and eventually ends up falling in love, even though they come from two completely different worlds.