Mysterious Wall Footprint in the 7th Lunar Month

It was a normal workday today. A guy in the office, let's call him A, went to get some printer paper. Suddenly, he turned left and looked towards the wall. He discovered a footprint had suddenly appeared on the wall. So, everyone started grabbing their own shoes or slippers to compare. When the smallest-footed girl in our office tried hers, It was even smaller than the footprint. Everyone looked at the shape of the footprint again, And suspected I had done it. So I compared mine, and it was clearly not me. Everyone took turns trying. Then they asked if I had secretly taken someone's shoe to make the print. Since I was the first one there. Later, they went to ask the person who left last. Unexpectedly, that big brother directly walked over and said, "Anything can happen in the 7th month." Everyone burst out laughing, and that's how the case was closed. Although I feel a bit sorry for the spirits, They really went through a lot. I still find it hilarious.