
Continuation:
By the way, I forgot three details. We know that Keirean wasn't killed by Ruve in 1st timeline because he's present at Tia's trial. And Ruve is shocked to see that Keirean is not defending Tia. He was planning to use Keirean's defense to save Tia, supporting his defense against the nobles' faction. But with Keirean staying silent, Ruve is trapped and cannot get Tia a lighter sentence.
Tia wounds Ruve in a fit of rage, and it's obvious she doesn't understand how she could have done this. Knowing Tia, it's also hard to believe she could do that, even to her worst ennemy. It's because she was also poisoned with the same poison Ruve had been fed. I mentionned that fact when she got angry at Jieun, but in the manhwa you can clearly see that on the morning of the stabbing she was completely unable to sleep the night before, so the poisoning is getting worse. Her stabbing Ruve was actually also Duke Jenna's will and doing in a way. Both her and Ruve were not in their right minds and not the masters of their destinies anymore.
Last detail, on the day of the execution, this is not portrayed in the manhwa, but Ruve was moved by Tia's tears when she looked at him. Ruve briefly regained his sanity and wanted to stop the execution. He was lifting his arm to stop the executionner when Jieun hung on his shoulder and arm, preventing him from doing so. And the axe fell and Tia died.

Here: https://forum.novelupdates.com/threads/the-abandoned-empress.43439/page-20
I don't know what page EODEZ started revealing these spoilers but I'm gonna read back for sure!! This is enlightening!!

Sorry for the Allendis fans out there. Even the one who summarized the novel said this: Don't read his POV if you're an Allendis fan.
Allen is a Yandere to the core. In western terms, I would go as far as call him a sadist and a psycopath. In his POV we discover how Allen fell in love with Tia because she has PTSD and is nearly mad with terror. He finds her trauma beautiful, and wants her madness and obsession to turn to him instead of her father. When Keirean tries to protect Tia from him, he thinks of killing him. He offers a ribbon to Tia, and after she starts to be healthy again he thinks of strangling her with it, in order for her never to change and keep the memories of her looking only at him. There is the moment in the carriage when in the manhwa Allen kisses Tia's hand. In the novel he kisses her on the lips, while she's sleeping - so unconscious and very much unconsenting. This moment gave off heavy creepy vibes. Allen also spent years building a house for Tia somewhere, and after she rejects him, he actually starts leading her out of her way home, planning to kidnap her and keep her locked in the house for the rest of her life. He renounces his plans at the last minute. His POV is extremely disturbing. Lots of people actually felt filthy and frightened after reading it. At this point in the novel, I was quite happy to see Allendis disappear from Tia's life for good tbh. :sweating_profusely:
Don't get me wrong, Allendis never did those horrible things, and he realised he was sick and left to protect Tia. He's not a villain. Yet, this is too much, and I really hope the manhwa doesn't insist too much on all these details for the sake of Allen's fans. I think it's enough to know he's Duke Jenna's ally and spy. I've seen the raws, so I know this will be portrayed in the manhwa. And I think it's largely enough to explain to the fans why Allendis can't end up with Tia.
CTTO: EODEZ

Um, can I read the novel? Do you have a link for me? I’m so interested now! Cause I never knew about the poison but I was definitely suspicious about his personality and character and his overall contradictions from the first life to his second life. I’m so curious now, I gotta read it in my own!
Plus, this poison, sounds almost like a drug, were it can fu** you up. Make you made even. Cause I noticed there was definitely some form of crazy in the air, not just for the prince but also Tia.
Ps : I've also read 1st timeline Ruve's POV and death, and it was quite heartbearking to see how his mind and sense of reality were completely broken by the poison. He was not able to discern what was real from what wasn't, who were friends and who were foes, and his paranoia was fed by Tia's emotionless attitude. We can see how he desperately loved Tia, and each time he clunged to the tiny smiles or emotions she showed to try to regain his sanity, only to be drowned in despair, anger and madness when she pulled her social mask back on again. He hated and despised himself so much that he thought Tia could never love him and that she was disgusted to be touched by him because of his commoner blood. He thought he was soiling her when he was touching her.
He didn't kill Keirean after Jieun's attack, he just said this to Tia because he thought she was leaving him because he couldn't give her chidlren anymore after she was declared barren - so he had become useless to her. He really wanted their child to be the next emperor because he truly believed she was the only one who could raise the future emperor. He knew Jieun was unfit to be the mother of the crown prince, and he was feeling guilty to think this because he was supposed to love Jieun, as she was the only one who was warm to him and saying she loved him. He was disgusted with himseld to be drawn to a woman who was so cold to him and only saw him as a political tool and a breeder, when he had a woman who loved him. (Ruve is definitely a one-woman man, it utterly broke him and his sense of honour and self-respect to have two wives.)
When Tia comes to plead for her father's life, Ruve loses it because she comes with just a pin in her hair. She doesn't wear the tiara she's always wearing and that only royals should wear. It shows that she is his queen and his wife, and she has removed it. He thinks he has completely lost her and that enrages him. [2nd timeline Ruve sends Tia a beautiful music box with a silver haired girl wearing a saphire and diamond tiara for her coming of age, after she publicly rejected him and their engagement. It is his way to say he still hope she will one day be his empress. So the tiara is an important symbole in the novel.]
When he falls from a cliff after being wounded and surrounded by soldiers he sees the moon (the moon is the symbole of the empress) and for him it's Tia who comes to him. He dies only thinking of Tia and all the things he could never tell her and ask her. He just hope she's happy where she is.
CTTO: EODEZ