
SPOILERS ALERT
(ANOTHER ALERT! APPARENTLY THE INFO I actually acquired is nowhere near a 75% correct (I'm sorry for this), The only spoilers that I gave and can confirm is that the Queen did die and that the concubine did use black magic.
Someone shared a link to a much reliable source below, so please check it out if you are curious! (Thanks btw!)

Okay! Here goesss
SPOILERS ALERT!
About the Queen: She will die from sickness, thus her fate remained the same as the story (that is, according from the link, however I do not know what the sickness is).
Truth about the concubine: He was an archmage and also immortal, and once had a man he was inlove with, but the man died, and so the concubine tried any method to kill himself. However, the King is the reincarnation of that man the concubine love, and used black magic to lure everyone to love him or something. Apparently, the black magic is eating is life force(?).
About the prince: The prince real father is the concubine. The King had or forced(?) the Queen to be pregnant by his concubine, and the reason for that was so the concubine can have a clown of himself. However, I do not know exactly how the prince will be the concubine's clone. I think the other reason as to why the king and the concubine planned this is because the prince will then have the blood of the royalty from the Queen, and also have the bits of his concubine. Sooo, the prince will then be the King's new lover after the the black magic has completely eaten the concubine's life! Very disturbing and disgusting...
The plot is very interesting and I do not fully remember the ending, but they said that the maid will go back to her original place along with 2 handsome guys(unsure about this too), and about the King and the concubine, they said the two will not get any retribution or something.
I'm not really sure about this tho. All the info and spoils I wrote came from the people who gave it out from the link I shared. So credits to them and thanks! (=・ω・=)
If you need confirmation and other info, please click the link.

Please don’t pass that link around. The first few pages of that spoilers page are riddled with false info. Always check the entire thread. If you’re too lazy:
https://forum.novelupdates.com/posts/5762864/

Hello! Thank you so much for informing me about this! I was actually quite unsure about the spoilers that I thound but I thought at least I have spoilers that I can share to others, especially after seeing a few disturbing truth about what the concubine did. I'm really sorry for not thoroughly examining the other pages, I'll try to be more cautious next time. I wasn't really expecting that others would actually spread false spoilers. Should I delete my post as to not mislead others or just leave it as it so that they can see your reply?
The novel is actually a good read. I've finished reading the available chapters and dang, it was satisfying fo see how things go. The emperor was such a pitiful lad, really. Pitiful, but I'd say he deserves it. I don't really know if the Rashta did something that made the Emperor like her so much, but what he did to the Empress was idiotic.
Rashta had a very depressing past, but instead of making good use of her experiences, she let her greed guide her. She wasn't very intelligent, but she's cunning when she wants something. I almost cried for her children. Her first born was so beautiful, and the Emperor truly did love her second child. But then I guess, it's better to have the story go the way it is now, at least, the Empress got what she truly deserve.
Will the first born arrive at the palace? And how did sovesht reacted when he knew that trashta already had a child before?
SPOILERS ALERT!
The chapters I read was not translated well so I can't assure that my answer is 100 percent accurate.
A faternity test was held for the princess (the child Rashta is carrying now in the webtoon) and the Emperor. The results showed that the princess was not the Emperor's daughter and instead was Rashta's past lover( the one who abandoned Rashta). Also, It seems like Rashta asked Duke Elgy( or something, he's the duke and seems to be Heinley's close friend, and also the man who lent Rashta money) to kidnap or hide her first born (Anh) or have someone kidnap(?) him, any way that can get Anh far from the Emperor. But then Duke Elgy came up on the scene, carrying Anh. Everyone has there attention on the Princess and the fact that Rashta deceived the Emperor so I couldn't
really say anything about their reaction when Anh showed up, and with the Emperor too, but I'm sure that he was really upset, like really really upset.
That is the only scene I've read where Anh was shown to the public, but I think there was a scene where the real father bought Anh to Rashta, but I'm not too sure, but eother the father or the grandfather gifted Rashta with his son's hair, and the Emperor saw the hair inside the envelope and knew that it's not Rashta's hair, unlike to what she said that she cut her hair out of boredom.
Another is, Koshar (Empress' brother), delivered an information to the Emperor that Rashta had a child. Koshar knew this after beating up the grandfather of Anh and forcing him to tell him Rashta's weakness. This lead to the Emperor ordering for Koshar's banishment because the emperor is trash and stoopid. He wants to cover up for Rashta.
About the Emperor's reaction, he had information about Rashta's past, but the translation was hard to read so.... I guess he was wary and his suspicions on Rashta grew. And when Duke Elgy showed up with Anh during the Faternity test, there was no significant reaction from the Emperor, or maybe it's just the translation.
Sorry if it's too long, I tried to give anything that I remember that is connected to the first born.
AND FEEL FREE TO CORRECT ME PLSSS
I binged read the whole series, and I'm forgetting a lot of parts.
Oh my god, thank you sooo much for the effort in this (づ ̄ ³ ̄)づ I got to learn so much. At this point i dont even care about those shit couple, with all the things they do, and just want to see navier happy (▰˘◡˘▰)
Waatt oh my goooddddd cant wait for them to arrive hahahaha. Wait, so that means the baby will be gave birdies too? That would he interesting hahahahahahahaha
Will be half birdies*
Yiiiieee I KENAT hahagagagagaga i bet itll be such a sweet moment and the prince will be soo cute and charming