In the heart of Beijing, a brother and sister, both in their early twenties, find themselves alone and horny. They start a raunchy chat, the sister using her best seductive voice to tell her brother exactly what she wants him to do to her. The brother, already hard, listens intently as she guides him, telling him to touch himself, to imagine it's her hand, her mouth, her pussy. He obeys, fucking his fist until he cums, his sister watching and touching herself, their taboo encounter leaving them both breathless and wanting more.