Ru Quan was terrified of the idea where his soul would break and he would forget everything about his wife again. From how the rest was acting, it was highly possible (It happened during the date with the food lady. He was in lots of pain and lost some memory of Bing Shi as a result). He ended up dead inside to a point where he had to borrow other people's emotions to feel something.
Ru Quan used to feed off the rage, the passion to live, the desire to be at the top, which Earl Fester felt right now. It was another source of fuel among many others. It gave him a reason not to kill off all the assholes in the world in one go.
