This has nothing to do with feng shui. This season is the peak of nesting and breeding in Ma Feng. In cities, it is not uncommon for Ma Feng to build a nest by the window of a building. Good Feng Shui will bring happiness and well-being, but the existence of Ma Fengcan will only bring you danger. It's like a time bomb, you never know when it will bite you. Therefore, it is suggested to poke it off with a stick at night, which is easy to remove before it "grows".