YBC is Si Ying sister from 10.000 yrs. ago, her name is Mo NV.

The orphan demon children Si Ying and Mo NV are 2 demon kids who rely on each other. TH Dad, the previous God of War, Tianhao, MY’s Shizun, caught  Si Ying & Mo Nv brought them the heaven realm to be made into walking corpse soldier to suck Demon (her own kind). Si Ying was abt to be selected but Mo NV stepped forward told Tianhao that she is stronger and will be more effective.

Si Ying was spared and Mo NV was thrown into the Fire Pot and her Demon essence is sucked out by Tianhao. Demon god 1.0 killed Tianhao saved Si Ying and brought her back to his palace. Mo NV body conditions is too dire and can’t be saved. DG made her into a weapon umbrella and gave it to Si Ying. SY becomes the devoted right hand to DG 1.0.

During the battle of Demon and God, U saw Mo NV came out fr Si Ying umbrella. She was attacked by Chu Huang and God of time; her soul was injured even more. DG 1.0 sent her to mortal world for 10.000 yrs. as mortal to repair her soul. In each of her reincarnation, she must experience injustice and suffering to repair her soul over and over again. Her reincarnation finally completed 10.500 yrs. later and her soul is fully repaired and she can return as Mo NV. 

So that’s the story of and remember Mo NV is only a kid when she had to experience her sad

I see, this make perfect sense. This is not in the novel. Good to know they have added Mo NV as part of  the immortal arc, her role quite crucial.

Yes she is v tragic for 10.000

Years. I thought this is a v good closure for her.

Thanks kwanto. I wanted to know Si Ying's story and this explains everything. The 2 sisters back story is really heartbreaking. 

Yes the drama is giving everyone a full character rather than the novel

How did you know this 🙄 why does she has to go through 10000 years with crappy life to go back being an evil spirit lol? Also I kinda don’t like it, it sounds like love and redemption and their silly 10 lives lol. Like I know her soul is broken, but if she was a goddess, sure… but she isn’t…. The story don’t feel very compelling. Anyway, we will see I guess

Really we're already despising her, now the writer gave her a tragic backstory, will we end up sympathizing with her? those tricky writers hhhh

It seems like the writer has given some background story for the main key characters so they don’t feel just a ‘black and white’ villain, and so we understand their motivation. For some viewers may not enjoy it, but personally I like grey characters and I am glad that Mo Nv’s story has been followed up.

 Megumi-H:

It seems like the writer has given some background story for the main key characters so they don’t feel just a ‘black and white’ villain, and so we understand their motivation. For some viewers may not enjoy it, but personally I like grey characters and I am glad that Mo Nv’s story has been followed up.

Multi-dimensional villain is more interesting. YBC in mortal arch is just bland, just like TTML for me not worth hating cause they just yeah not interesting. By the end of the drama, I’m curious what pp think abt her.

 kwanto:

Multi-dimensional villain is more interesting. YBC in mortal arch is just bland, just like TTML for me not worth hating cause they just yeah not interesting. By the end of the drama, I’m curious what pp think abt her.

Pretty much this. I haven’t seen MN’s arc yet, but it likes they pick the worst reincarnation of her and trying to make us interested in it. Think love and redemption, if this is their last life in their 10 lives redemption thing, we would stop watching lol. And if we have more time, she can have her own arc, but we don’t. She can be one of those SFL that we just FF lol

 Alila Nguyen:

Pretty much this. I haven’t seen MN’s arc yet, but it likes they pick the worst reincarnation of her and trying to make us interested in it. Think love and redemption, if this is their last life in their 10 lives redemption thing, we would stop watching lol. And if we have more time, she can have her own arc, but we don’t. She can be one of those SFL that we just FF lol

Let's discuss again when her story ends, not like she is going to get HE anyway. Yes a bit like L&R but hers is like 170x instead of 10x and each time is the same thing. Quite the contrary to many pp I like the immortal arch pacing,  I'm absolutely hate dramas that do not progress. And really in the side characters of TTEOTM don't take as much time as other side characters in other Xianxia. You are shown what you need to see and that's all. U won't see GY tries to court LSS much either, I also believe Mo NV - GY time will be cut a lot to make ways to the plot. 

With the reduction of ep., I really wonder how in-depth they can develop Mo Nv and GYJW. However it’s an interesting contrast from TTJ and LSS story, they seems to hold more of a tragic and unrequited love. Let’s see how the drama has been edited to the end. No expectation.