It was never mentioned how Athy was able to "reincarnate." I believe this is a novel plot hole that Plutus & Spoon is trying to fill in this webtoon version.
The Jeannette sacrifice thing might be a fanfic because there was never an incident like that. She does possess black magic in the novel in which she unconsciously charms people. It went berserk near the end of the novel, when Claude told her she's not his daughter, and caused an explosion. This leads to her & the Alpheuses' banishment (yes, including Ezekiel).
Again, this is all novel things, so the events might not hold merit in the webtoon world, but they do provide insight.
The webtoon is no longer similar to what went down in the novel, so there are events in the current story which might have been newly added by Plutus & Spoon.
Although if you are curious novel-wise, Anastacius' character has long been dead. The original antagonist in the novel is Caraks who is Aeternitas in disguise. Aeternitas was an Obelian king, the one Lucas refused to teach. His sole purpose is only Lucas, (you can say he's a fanboy but got rejected) and he realized along the way that Athanasia is somewhat important to Lucas that's why he messed with her as well.
Novel-wise, Anastacius was indeed a trash. He was jealous of his younger brother who clearly is more powerful than him when he's supposed to be the next king. That's why he seduced & co-planned with Claude's ex-fiancee Penelope the whole black magic fiasco which resulted to Jeannette being born.
In this webtoon, however, there might be new revelations considering it took a different path plot-wise.
well, for starter they are both prince who fought for the throne.. anastacius grew up with people who taught him hatred and jealousy.. his mother abuses claude, and his relationship with aeternitas made it worst..
claude is a genius magician, one thing that a king must possess.. claude is good at everything even though he is treated as shit in the palace because of the empress.. people also think that he is more suited to be the next king instead of his older brother who is very dependent to his mother..
anastacius hate that he is being compared to a "shit" claude.. even though he is not really a bad person at first.. but slowly bit by bit his jealousy and the influence of the people around him made him in a very twisted person.. to the point where he had sex with the fiance of Claude.. the mother of Jeanette.. he also fully accepted aeternitas and used blavk magic to show others that he powerful too..
claude new that the kingdom will fall into ruin if anastacius will rule over it.. that's why he killed everyone who supported anastacius and defeated him.. he stole the throne from anastacius..
after many years.. anastacius returned to take the throne again from claude.. but he can't just kill claude and athy that's why he used the curse and Jeanette's influence, and made claude and athy relationship bad.. so claude will kill athy (who is also a rightful owner of the throne in the future) and kill claude after athy died..
well, for starter they are both prince who fought for the throne.. anastacius grew up with people who taught him hatred and jealousy.. his mother abuses claude, and his relationship with aeternitas made it worst..
claude is a genius magician, one thing that a king must possess.. claude is good at everything even though he is treated as shit in the palace because of the empress.. people also think that he is more suited to be the next king instead of his older brother who is very dependent to his mother..
anastacius hate that he is being compared to a "shit" claude.. even though he is not really a bad person at first.. but slowly bit by bit his jealousy and the influence of the people around him made him in a very twisted person.. to the point where he had sex with the fiance of Claude.. the mother of Jeanette.. he also fully accepted aeternitas and used blavk magic to show others that he powerful too..
claude new that the kingdom will fall into ruin if anastacius will rule over it.. that's why he killed everyone who supported anastacius and defeated him.. he stole the throne from anastacius..
after many years.. anastacius returned to take the throne again from claude.. but he can't just kill claude and athy that's why he used the curse and Jeanette's influence, and made claude and athy relationship bad.. so claude will kill athy (who is also a rightful owner of the throne in the future) and kill claude after athy died..
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