SASSY

He isn't HAHA I'm pretty sure in one of the first few epidodes when the QD was tryna be sacarstic with cheoljung she said something along the lines of her treating cheoljong like her own son even if he wasn't...hmm not sure about the poisoning part though...

Any secondary couple?

HAHAHA it's the same thing here!

TRUE DAT!!!

Nope, the late king was from the kim clan cause his mother was the grand queen dowager (kim clan). His wife who is the queen dowager is from the jo clan.

YASSSS!!! I loved the part in the original chinese version where the king was holding court and his son just started playing and running around....

The plot seemed really similar but the characters not as much...The ML smiles wayyy too much in this remake XD I skipped to the ending too and it was 95% similar to the original chinese version. ..

Any secondary couples?

He only sleeps w the FL. His harem was basically useless.

There is a third ending which is definitely wayyy happier than the first 2...you might be able to find it if you search it up.

That ending was.... lacklustre. I preferred the endings in the chinese version.

Grand queen dowager (GQD) is from the kim clan. Queen dowager (QD) who is from the jo clan, married GQD's son who was the king before Cheoljong. Both kim and jo clan are fighting for/wants to control the throne. Not sure how GQD is related to cheoljong but I know for sure QD is not related to him at all. GQD and Kim so yong are from the same clan (Kim). QD and jo hwa jin are from the same clan (Jo)

What are the differences between the original and the remake?

cool got it thx!

That makes perfect sense!

It was indicated

*whispers* i think it's dead....

I will try to answer some of the questions based on how I inferred it XD
1. The hair demon hated the princess for stealing the man she loved and hence had always wanted to kill the princess since. She was released either by He shou ye or the princess herself with the mission to kill the princess in order to activate the demon serpent.
2. Not too sure about this. But I'm guessing Boya took over the role of the vermillion bird and became one of the 4 spirit guardians? Anw he was probably a. Just unconscious (and the spirit guardian was just his subconsciousness) or b. He is still a spirit guardian (cause at the end of the movie, he could have gone with Qingming but he remained at the imperial palace cause the main job of the spirit guardians are to protect the imperial palace, also he suddenly was able to conjure magic when he wasn't able to before LOL). I came to a conclusion as I was typing this, the answer is probably b.
3. As explained above, Boya became a spirit guardian yes (I'm guessing), but not of Qingming. The spirit guardians were...well, spirit guardians of the imperial palace (remember? the 4 spirit guardians were located in the imperial palace to barricade the demon serpent from leaving the palace). Those that had to be released by Qingming through the talismans are called demon servants.
4. There was probably a mistake in the subtitles cause chinese is my mother tongue and I'm pretty sure I did not hear her say mermaid HAHA. Anw she's able to stay 'immortal' cause either a. The demon serpent in her kept her young (not sure how maybe by feeding off her desires?) or b. That was not her original body (cause at the altar He shou ye asked her how many times she had to go through the pain of purging(?) /giving birth(?) to the demon serpent and she basically said many times. So unless she's been 'eating'/'swallowing' the snake after every 'birth'/'purge' like what he shou ye did, I think the snake just went to look for a new host/vessel? This one's a wild stretch HAHA cause it does not really explain how the demon serpent was able to transfer her memories and consciousness to the body of the host, and how it did not affect he shou ye other then granting him immortal life.....I'm more inclined towards option a. at this point.WHY DID THEY HAVE TO PUT IN THAT ALTAR PART AND NOT LINK IT TO ANY DAMN THING IN THE MOVIE UGH! Making my mind work thinking about all the possibilities...
5. I did not even realise how until you said it...probably a plot hole? I mean who would have thought that the insides of a demon serpent are rocks amongst rocks lol...

ehhh It was pretty good but not the best...I mean I was able to keep my tears from falling so...XD

Got it thx XD

I too have no idea bout that haha...but I’m guessing it was that black thing that jumped out of the box in the first few episodes...