SPOILER FOR LUNA II ARCHON QUEST. SCROLL PAST IF YOU DON'T WANT TO GET SPOILER.
The discourse around Rerir made me realize that it's not that Rerir's morally grey character is new in the game's story, it's that it's just how many world quest characters are written, only that Rerir (forgive me if I'm wrong) is the first kind of that character that is displayed in the AQ.
One could argue that Dottore, Raiden, Wanderer, and many more villainous characters are written like that as well... I concur with the argument actually. It's just... there's something about how damnably and awfully realistic Rerir's-- and by extension Tholindis-- action is? On how a 'nobody, common' person could be complicit with something incredibly awful?
I think Rerir and Tholindis' 'selfishness' is the point of the story. Wishing for a normal, unproblematic, unconcerned with society kind of life is something normal to do. Sometimes you just want to live your lane without society's bullshit breathing down your neck. Sometimes you only want mundane problems to be your only problems. As Rerir said it, they don't have grand ideas of 'saving the world' and such, they just want to live in peace.
However, because of their circumstances, Rerir and Tholindis's wish is selfish. Rerir was an orphan, groomed since childhood to be a disposable weapon for Irmin to get rid off a bloodline. He didn't enjoy it, true, but his wish for a normal life with Tholindis stopped him to rebel, because rebelling would risk ruining everything he had with her. He only wanted to marry Tholindis, but because of his existence as an assasin, this wish is a selfish one.
I see people argues that Tholindis is just as bad as Rerir. I see the point of their argument, seeing that she did kind of ignore the genocide against the Crimson Moon dynasty despite hailing from the bloodline too until it could personally affect her. I have an opinion that it's not entirely true; For one, Tholindis's situation is more precarious because she was the part of the hunted group and was one of the researchers in the Universitas Magistrorum. Hell, remember that the Magistrorum was chaired by Hroptatyr, the most favored sage of King Irmin. Being a member of an educational institution chaired by King Irmin's man means that her actions as a researcher was exposed to more scrutiny than an ordinary person, so if she did anything risky, the risk is greater for her because she could be ratted out by the Magistrorum.
Second, Tholindis did try. She tried. she helped the pink-haired girl to escape. But that's not all. Her opening a gate to the 'moon dimension' is her trying to help. Remember, while it was extremely brutal and vicious of King Irmin, his hunt for the Crimson Moon members wasn't entirely unfounded. They did have something special in their bloodline. Arlecchino, in her teenagehood and without the supervision of her bloodline's technique or training, managed to kill a harbinger 1 vs 1. Imagine an army of her. Once again, I'm not justifying King Irmin, it's just that the Crimson Moon bloodline does impose some risk. However, killing every members and even children is definetely not a sane option.
I think Tholindis understood this, so in a way, her researching the Crimson Moon and jumping into her reflection is her trying to find the root problem (as she perceived it) of its all; the Crimson Moon's power. Perhaps, she thought that if she could conquer it, the power that made her bloodline be hunted could cease to be, and King Irmin would leave them be. Of course, it's doubtful if King Irmin would stop even if the Crimson Moon's power cease to become a threat, but Tholindis believed that. She did say that she knew a way to stop 'all of this'.
In conclusion about their characters, I repeat once more that in my opinion, their selfishness is the point. Even a simple wish of a normal life is considered selfish if you live in tyranny because your very existence could support said tyranny.
Now I wish to move to other world quest characters who are written similarly with Rerir; a lot. Too many for me to list one by one😭 but I wish to talk about Rene and especially Och-Kan (surprise surprise. Who would have thought.)
There's a narrative reason why Sandrone retold us the Narzissenkreuz story in the epilogue; Rene is the antithesis of Rerir. Unlike Rerir, he wished not for a normal life; he wished to save the world. His dream grand, and instead of being a cog of the machine, he led and built that machine. Unlike Rerir, every actions that he took were made out of his pure free will; experimenting with his friend/coworker's body, building a cult, letting himself to be... uh, whatever entity he ended up to be, was the results of his own ambition to live up his wish to become a hero. In his childhood, he was often relegated into the 'evil dragon' role, so his yearning to become a hero bled into his later life.
But in the end, his wish was just as selfish as Rerir's. He fucked Fontaine's society and hurt his friends under the belief that he was the sole saviour of them all, not believing that other people could be of any help if not by acting as his tools and pawns. That's why Caterpillar called his motive as a 'mental illness' and Sandrone is so critical of him; his wish to save the world is selfish.
And there's Och-Kan. If there's any character who deserves to be under fiery scrutiny worse than Rerir, it should be him. Arguably, he was way worse than Rerir; he was King Irmin's equivalent. He was the top of the society, and he used his power to enact genocide against the previous ruling force (in this case, the dragons) even if the members he hunted had no link to their predecessors' sins. He did heinous acts to aid his goal; inhumane treatment of the workers who excavated the tunnel to Ixlel's place, with much of them, if hadn't driven insane with the eldritch aura or starved, were scorched by Och-Kan's turnfire; enacted military violence against his people; directly or indirectly involved in the death of his oppositors, like Lianca, Ahpub, and Ixquieh; and so much more.
And was what his goal again? Oh yeah, to 'save humanity'.
But then again... Och-Kan was frighteningly human, even with his heinousness. He wasn't treated humanely in his childhood and constantly suffered the Flamelord's Blessing. His wish was to become human, and he veiled it under his wish to save 'humanity', which I interpret as an idealized state of humanity, the one who accepted him and love him unconditionally.
Case in point, world quest characters are written the same as Rerir; terribly, awfully, horribly, human. They did their actions because they have a wish, be it a normal life, fulfilling a childhood dream, to have an unconditional acceptance by society... all human wishes that I believe almost everybody have in some points of our lives. Its just circumstances had made that their actions have far larger consequences than us, 'ordinary' humans.
Hmm... all this discussion makes me wonder if King Irmin was rather the same, especially with Rene and Och-Kan; he had good intention, or was under the delusion that he alone could save the world. From his name alone, it's implied that he had something to do with Irminsul, and who could say that he didn't saw the Irminsul's shenanigans, and the knowledge of all past civilizations and events erased from the world didn't drive him crazy? That it fueled his 'saviour complex', that 'I did what I did to save you all'?
Who knows. Let's see the future versions to see how long this would hold up.
I think some people couldn't stand that beyond their heinous actions, the 'villains'-- people they deemed evil-- have the same drive and wishes as us. They don't want to acknowledge that they're the same as us and that we have the capacity to become like them. They couldn't imagine that they could stand in the 'villains' shoes, so the 'villains' must be extremely evil, far removed than 'normal people' like us, or the other end, that they're 'good people', extolling, exagerrating or straight up made up their 'goodness' because their defenders couldn't stand that they too could be 'evil'.
Again, don't take it as justifications of what they've done. This is just a cent of mine in their discussion. Frankly, I enjoy the discourse because it opens you up to different perspectives and interpretations. I think my math teacher said it the best; since we couldn't live all lives, we consume books (or in our case, fiction) to live through the characters' shoes. Its to raise our understanding-- not necessarily sympathy, just understanding-- of why things happen and why certain people in the world act they way they act. It could serve as a warning, for us to not follow their examples and be better people, or a call to sympathy for people in their situation. Fiction is not a morality contest, it's just a tool for us to better understand the world.
Tl;dr: Rerir and Tholindis's 'selfishness' is the point. It's to showcase us how 'normality' could be a weapon in broken society like Khaenri'ah, because your very wish of a normal life could support the ill of society. Their character writing is reminiscent of world quests characters, who arguably are morally grey.
As a closing statement, first of all thank you @erikaslumbers for our discussion that fuelled my thinking about these characters (I love you so much twin🥰). And second of all, witness: