The strange incident began in an ordinary day. A younger sister was waiting to be reunited with her older brother after a long time, when a strange woman appeared and introduced herself as "your brother's girlfriend." She approached with a friendly smile, and her guardedness was easily relaxed... For some reason, the younger sister felt that she had a similar vibe to her, and she ended up letting her skin touch her... It was then that she discovered the shocking truth. The story of a twisted family was about to begin...