As Super Chen said, after the spirit sword exchange meet between No. 60 High and No. 59 High, the black cat called Zheng Tan became a cat overlord in the area, and Zheng Tan's small "independent regiment" developed into a dozen or so military divisions.
Zheng Tan had never imagined in its entire life that it would have so many troops.
With the increase in the number of cats under Zheng Tan, business naturally started to expand rapidly. Zheng Tan's pest control team was now very large; in Songhai at least, there were no longer any human firms that could compete with the cat regiment led by Black Tan – cats were innately talented at catching the quick little pests to begin with.
Zheng Tan's pest control team had now expanded overseas, and Zheng Tan even gave itself an English name: Lee Zheng Tan. It had no choice but to follow the trend in order to make foreign connections.