One key element is their origin as men. They were given Rings of power by Sauron. Another is their corruption. The Rings slowly turned them into wraiths. Also, their loyalty to Sauron as they were bound to him through the Rings.
The key elements start with their pre - Ring days as powerful men. Then, the moment they received the Nine Rings, which was a turning point. Their subsequent transformation into wraith - like beings due to the Rings' power is crucial. And finally, their role as Sauron's servants in the hunt for the One Ring.
Well, first of all, their human origin is fundamental. These were not just ordinary men but had status and power. When Sauron presented the Rings, it was like a Faustian bargain. They started to change physically and mentally. Their physical forms became more and more insubstantial as they were drawn deeper into the power of the Rings. Their unwavering dedication to Sauron's cause of retrieving the One Ring is also a major part of their back story. They became the embodiment of fear in Middle - earth, a constant threat to those who opposed Sauron.
Chapter 410, "There's Something Wrong with This Lottery Box!", is the clearest early answer because it turns Sister Li's situation into a concrete plot event. Early on, Nina's voice had barely fallen when Pan Xing turned his gaze to Jiang....
Chapter 304, "Shh, Let's Not Disturb Big Sister", is the clearest early answer because it turns Big Sister's situation into a concrete plot event.
Chapter 182, "Director Sun Still Knows How to Stir Things Up", is the clearest early answer because it turns Su Yinwan's situation into a concrete plot event.
Chapter 448, "Has Jiang Li Gone Crazy?!", is the clearest early answer because it turns Notification's situation into a concrete plot event. It opens with Yu Li still wanted to persuade her, "Why not keep everything? and closes on Having her on his team was like having dead weight..
Chapter 138, "From now on, let's get to know each other again", is the clearest early answer because it turns Director Sun's situation into a concrete plot event. It opens with Is there such a good deal? and closes on Could it be that the poison also had a side effect of making a person....
Chapter 311, "Signed Jiang Yan", is the clearest early answer because it turns Jiang Li's situation into a concrete plot event.
Chapter 251, "It seems that going on a transformation show is really useful!", is the clearest early answer because it turns Fang Wenzhe's situation into a concrete plot event. It opens with If Du Qinglian was somewhat angry just a moment ago, now she was...
Chapter 199, "You Found Out Long Ago?", is the clearest early answer because it turns Zhao Lang's situation into a concrete plot event. It opens with Damn, the production team is actually being so generous this time,...
Chapter 474, "Handcrafted Wooden Bed", is the clearest early answer because it turns Brother Pig's situation into a concrete plot event. A useful checkpoint is the way the scene starts with Although everyone besides Jiang Li and Shang Shuyue was red-faced and...
Chapter 639, "Young Master Gu, Does Your Family Need a Dog?", is the clearest early answer because it turns Pei Ye's situation into a concrete plot event. The chapter turns that into something concrete by moving from Half an hour later, Jiang Li pushed open the door and walked out.