A slender older sister named An works at a mahjong parlor. One day, she accompanies her boss to a mahjong game where she meets a man visiting the parlor for the first time. As they continue playing together, he becomes increasingly attracted to her kindness and starts spending more time with her. Their relationship evolves into an intimate affair after trying strip mahjong. They spend the night entwined, their bodies becoming one again and again like a game of mahjong. The twists and turns of their passionate connection remain to be seen...