i guess i could take the time to explain a little bit about one of my self inserts for the donghua, throne of seal + also talk a little bit about throne of seal in general.
This is Scyllaria (any pronouns, but usually defaults to she/her), who is definitely more oc than self insert. She used to be a high ranking demoness. In Throne of Seal, the power hierarchy of demons are by numbered pillars, of which are 72. Scyllaria was the 14th Demon Pillar - the Demoness of Pride and Justice. She used to serve the demon king, Feng Xiu, and helped wage war against humans since the event known as 'The Descending'. But in the latter years reaching to the 3101st year, she was starting to see the toll the war took on her own kind and demon soldiers. Even with the passing years and having her strength be tested time and time again against old familiar demon hunters, and new ones too - she starts thinking about whether or not this war is even worth it anymore.
Ultimately what causes the camel’s back to break is when one of her high ranking officers/understudy is mercilessly killed by a fellow High ranking Demon Pillar who viewed her understudy’s orders of a military retreat to be the ‘coward’s way out’, and thus killed them in front of her. As mentioned this is the event that causes the camel’s back to break, and Scyllaria in response declares that “This war is not worth the cost of our comrades…” and strips of herself her own Demon Pillar Crown. A Demon Pillar Crown in Throne of Seal is like the source for all of a demon’s powers, and would usually result in a demon's death if their 'crown' or 'core' is destroyed (or you can incorporate it into your furnace which is a knight's power source).
However since she is dethroned herself of the crown, it ultimately doesn’t kill her, but it does mean the loss of most of her powers. This means she’s got a fraction of strength and power that she once had. She is more powerful when compared to the average human who’s a Demon Knight, but not powerful enough to say go toe to toe on her own with any of the high ranking Demon Pillars. Think of it like a level 50 character having their power reduced to say level 18. Even if by some miracle Scyllaria got her demon crown back and her power restored to what it once was, she would only ever be able to land a small cut on Feng Xiu.
With this choice, she is banished to the human realm with nothing but her signature weapon, the clothes on her back and her pride in tatters. For some point in time she wanders aimlessly, doing nothing but living with the elements, trying to find peace with herself. There are lots of rumours and tall tales of a woman in blue with horns of a bull escorting lost hikers, adventurers, and novice knights survive against the elements. Many brush these off as urban legend, but many who have crossed her path swear to her being real.
Sometime 10 years before the events of Throne of Seal's first episode, a high ranking Demon Knight comes a cross a job listing for a local village that’s scared and terrified of something that’s hunting the local deer and wolf populations and those numbers are dwindling fast. The Knight with a small crew investigate and are surprised to come face to face with a Scyllaria - they've crossed swords before, but seeing a version of her alone in the woods is a strange site. Instead of resorting to violence, they talk.
The conversation eventually ends with the Knight taking Scyllaria in to the Temple Union, who for as much want the blue demoness dead - realise her knowledge and prowess could be a valuable asset in taking down the Feng Xiu and hopefully ending the centuries war with each other. She does accept this although it's not like she really had much of a choice to begin with, its not like she can go back 'home' anymore. Since Scyllaria's powers are not what they once were, she is begrudgingly promoted as a Knight, so that she can add other demon crowns to her own 'furnace'. To hide her identity as a demoness, a high ranking spell is placed upon her that changes her identity that removes most of her demonic features, and gets bestowed a fake name going forward.
Eventually Scyllaria would become a mentor figure to Long Haochen, although how or when that happens I have yet to decide (it's been a while since I've seen the show). Although when she does become a mentor figure, her true nature as a demoness isn't known until much later after the Siege at Exorcist Pass.
It should be noted that Scyllaria is a very gruff, almost kinda Frank Castle-like in that she is a pretty unpleasant individual to be around but deep down she does care. But it's never the 'maternal' type of care, more so 'i have to give a shit about you, because if not then who else will?'
UHHHH she's not really paired with anyone although many people do notice that she seems to act on more 'friendlier' terms with San Shui, who is a member of the Temple Union, but seems to be a little more willing to share some genuine sympathy for Scyllaria even if they were once enemies on the battlefield. I'm not sure how this hypothetical relationship would develop and blossom, but i think that bit of sympathy and just San learning about Scyllaria's doubts in Feng Xiu's leadership would be one of the root causes that brings them together a little bit.
