
I just want the mother to know what kind of bitch his other son was, what he put Seo-in just the realization of her face and despair is enough for me

I’m pretty sure she knows what kind of person his son was. She’s just avoiding reality for the sake of her “perfect family”
And to be honest she’s no better than him, cos she knew what was going on and still decided to turn a blind eye.
Tho I agree with you. I need to see her getting some kind of punishment for all the things she made Seo in go through

Wait I'm confused what's the connection with the Regas and the potion, family, etc.

- The Regas is the only being able to find/read the truth on I guess the black potion or something else, and they all appear as blonde twinks (hence why Abel has been twinkified)
- To find this truth the marquess' family (idk their name) tried to sneak family members in as Regas, but they never managed to make the connection with the dragon (I'm guessing it's necessary to be brought into that forest, and why Abel got killed so fast too since he could go in)
- The Truyde family has an ill-fated destiny with such Regas because while the Regas end up loving the king, the Truydes love the Regas in an obsessive manner (hence why the dude's always surrounded by blonde twinks that resembles the intended Regas of the king)
This is all I gathered from memory of the webtoon. I don't know the novel, so don't quote me on that xD

Spoilers:
So we know abel is the prince’s regas, the marquis or whatever his position is, has something that has been passed down in his family, which could be called the duke’s secret and the relationship it has with the black poison. Well, that item is a wooden pendant with a dragon engraved on it (same as the one previous Abel gave to Karas when he was about to die on the forest).
Later, Abel sees the past from that wooden pendant and thanks to that he discovered how the black poison was made. In the past, he sees that the duke’s family always had an obsession with the king’s regas, and so the duke’s father shared the secret with the duke when he was younger, that is, the poison is literally the duke’s family blood, and when he shares this secret he tells the duke that he has to eat him (his father) to create the poison and continue killing the next king in line and controlling him with this addiction, so yeah, basically the duke’s family committed cannibalism, and the black poison is black because of the rotten flesh that his family has been eating to pass the poison, hence, why the duke is also immune to the poison.
Sorry if it’s hard to understand, I read the story a few months ago and try to share the most important parts I remember:(
Ah at this point I want a bad ending like the last one. That they don't get together. It's unbearable to read now I feel so bad for Clauden