My Obsession

After the destruction of the Sang family, Sang Lan was picked up by Huang Que. A man named Thursday still lived in Sang Lan's body. After a mission by Huang Que, Thursday met a man named Wednesday. This mission also made Sang Lan meet a man named Liao Heting. Thursday and the Sang Lan brother and sister worked together very well. The four of them did not deal with each other at the beginning, but later became tacit in fighting. They worked together. The gang killed many man-made monsters called "Ku'E", but everyone had a purpose behind them. There were bugs in this world from the beginning, and many people's faces could not be seen clearly. Who is Huang Que? Why can he accurately know where "Ku'e" appears every time? Are Wednesday and Thursday the same kind of people? What is the definition of "Ku'E".