Ma tong li you yao guai

Simon is afraid to sit on the toilet. He is sure a monster lives inside - one that roars when the water is flushed. Little by little, he gets to know the monster. First, he tries to suffocate it by stuffing up the toilet with mountains of toilet paper (to which the monster replies with a frightening "Glop!"). Then he tries to get on its good side by throwing in a lollypop, and to make friends with it by parting with several little toys.