The sect master is certainly not happy

Fu Jie didn't actually have any problem with this man being a spy, however, he still couldn't help but feel a little weirded out by the fact that the sect master didn't trust Xiao Jingyi. 

He was her adopted son and she loved him a lot but she was still unable to completely trust him because of the demonic blood coursing through his veins. 

Fu Jie was never able to understand why but it seemed that the woman was almost sure that there would come a day when it would become almost impossible for Xiao Jingyi to suppress his demonic blood. 

The reason why she kept a spy was simply so that she could know if the man showed any such signs of sudden change, however, even if the man did show any such changes, she didn't plan on imprisoning him or anything like that, and instead, she planned on helping him. 

Fu Jie almost felt pity for the woman who was never able to protect her son like she had hoped to, in the original story.