After joining the company, Lin Zhixia moves into a four-person dormitory, never expecting to encounter a roommate, Du Xiaoman, who has made taking advantage of others a habit. From toothpaste and laundry detergent to lunch boxes, clothes, and group dining expenses, Du Xiaoman repeatedly tests everyone's limits. She keeps saying, "We're all colleagues. There's no need to be so petty," but secretly eats other people's lunches at the office, takes their coffee, steals their projects, shifts the blame, and even takes company vehicles out without permission, causing financial losses. Every time the others give in, she only becomes more outrageous. Finally, Lin Zhixia and her two other roommates decide to stop staying silent and expose Du Xiaoman's true colors with evidence. This time, nobody is paying her bill anymore.