In this short scene, we are introduced to Caixin and her younger sister, Xiaobai. Caixin's younger sister is known as "the big sister" because she is so strong and has a lot of good looks. The two sisters play a game of "grooming" with each other, which is basically a game where you pretend to be the other's friend and make the other act like you're the one who's been pranking Caixin. We learn that the big sister likes to eat snacks and that she likes to cough. We also learn that Caixin has an artificial arm, which means that she's going to have to wear a special outfit to play this game.