A man in his fifties, who is very selfish.
A woman in her late twenties, who can be quite naive.
The story begins on a mountain top.
Someone is wrongly accused of a crime.
It's a story about sacrifice.
Your character has to resort to underhand methods to achieve results

(Generated Plot that is irrily similar to the plot)

Onell, the wet nurse who can't have kids. (She's actually a super interesting character as well, she was caught by slavers in on of the neighboring kingdoms and may have something to do with coming wars, wags eyebrows). After the death of two of his childhood friends, she comes in (literally right before Marielle dies) and the effective exile from his other two best friends (the two queen's husbands) and keeps him from falling down a precipice of despair. So I guess where I'm going with this is a fully developed prequel that ends with the deaths. Another pang for Erion is that Natiselle (Marielle's daughter that Erion and Onell (raise along with one of Eline's sons)) looks very similar to Marielle.

Gov’t/Setting:

• - The Kingdom of Darion is a diarchy (so two kings as opposed to a monarchy). There are twelve houses in total, and everyone is affiliated with a specialty, think like a medieval guild or American style President’s cabinet (does Australia’s President have a cabinet?). The King Houses (if you can help me think of a better name then that, I would be eternally grateful) are in charge of War (Soldiers and Peacekeepers) and Coin (Econ). The ten remaining lord houses are things like medical, education, artisanry, agriculture, etc. The Houses are all named after the last name of the lords. They all have distinctive colors and corresponding gems, have offices in the grand palace (I can tell you more if you’d like, but I think that’s enough for this scene.)
  
  
• Characters:
• - Jerlorn Deracose is the Crown War Prince and has been friends with Marielle since they were 11 and 10 respectively. How they became friends is super complicated. As a crown prince, he is expected to get married to strengthen an alliance. He is about 16 at this time
• - Marielle is a common girl that became a lady’s maid to her friend Eline (part of the Education house) after her father (a carpenter in the Artisan’s Guild) died (during his conscription, so that’s awkward) inorder to support her family. She is about 15 at this time. She is known around court as being one of the most beautiful women.

Random

Blood dribbled from every orifice, living and dead, animate and inanimate. In the distance, I could see her, stark in her darkness against the setting sun. It seems that she was no exception. Blood streamed from her temple, dripping past her eyebrow and into her left eye. There were trails of coppery brown smudged against her cheeks, run through with fresh red trails. It looked as if she had given up on trying wiping it away. Her blades dangled at her sides, loosely clutched in her hands. “Natiselle,” her name seemed to bring her back from the brink of her personal precipice.

“Stris, I – I, I don’t know.” She shook her head, almost bowing in defeat.

I took her in my arms and she fell into me, her body shaking uncontrollably. For the first time in ages, I noticed how small she was. I cradled her blood soaked head on my shoulder, her temple resting against my cheek. Her tears were both silent and deafening in the same instance. “We are alright, that is all that matters.”

“I never thought it would be like this.” She whispered into my shoulder. “I only wanted our family back. How have I fallen so far?” Our bodies shook as she choked over her words. “I – I never wanted this.”

((Ooh, nice imagery. The blood, the sun, the grim tone –nice! A few things. This section really confused me: “Natiselle”, her name seemed to bring her back from the brink of her personal precipice. “Stris, I – I, I don’t know.” She shook her head, almost bowing in defeat. It's hard to see who's saying what. I assume that the narrator says Natiselle's name, then she replies, but the way it's written makes that a bit unclear. Remember, when changing speakers, change paragraphs. Very important. So it becomes:

"Nastiselle," I whispered. Her name seemed to bring her back from the brink of her personal precipice.
"Stris, I –I don't know," she manages to choke out. She shook her head, almost bowing in defeat.

Another thing that I personally didn't like (but it's stylistic, so it's not necessarily incorrect) was the phrasing of "For the first time in ages, I noticed how small she was, how small and seemingly frail." I would definitely cut "how small and seemingly frail" from the sentence. "Seemingly frail" is kind of an awkward phrase. I think leaving it as "For the first time in ages, I noticed how small she was," makes for more emotional impact and a smoother read.

Hey! This is nice! And I totally agree with everything that @wlyroft said, but I want to add a couple more things, things that are my own stylistic takes on it (i.e. you can ignore them if you want lol)
#1: the word "orifice" i had to look up and I don't know if thats just me being dumb or if it's a more common than I thought but using words that the reader has to look up or guess at the meaning is only good if you're going for pretentious sounding style (im not saying your being pretentious at all!!) just that using words that are too big for the audience to understand is frustrating. The good news is that everything else was perfectly readable, so it's not a widespread problem in your writing.
I get that finding the right word is hard! but that is what is so hard about writing–putting large, difficult themes and characters into the smallest, most understandable words.
#2: it sounds like Natiselle is in shock. (and i've never been in shock so i don't have a lot of room to say any of this so you can ignore it if you want) and if she's in shock than i don't think she's going to say a that much. Her dialog is kinda long in my opinion.
If i was writing it, i'd cut it to something more like this:

“I never wanted this,” she whispered into my shoulder, "It was never supposed to be like this. I just wanted-" Her voice broke, and she said through a sob, "I just wanted our family back."

But idk! both of those things could go either way!
I liked it a lot overall!! Good work!))

Aelina:

• She is from the Musical House (Toulerin) and is a harp player so she spends her days in the wealthy Pravaci district practicing.
• She has grown up with and been in love with Strisen (Kraio's twin) since childhood.
• When Natiselle integrates herself into court life (with the help of some old friends of Erion's) she is immediately suspicious because no one has heard of Nati before. It doesn't help that the first person Nati runs into (by design) and befriends is Strisen. Aeline immediately jumps to the conclusion that Nati is only looking to climb the social ladder.
• Because Nati's backstory is that she is from a provincial estate, Aelina's goal is to scare her away from city life by "accidentally" taking her though the roughest parts of the city. She had asked her friend to pop out and menace them once they had gone farther in. Her thought was that if this was Aelina's version of safe then, Nati would never feel comfortable away from home and beg her parents to recall her. A terrible plan through and through BC she never expected to be in any real danger.

Natiselle:  thanks so much the multifaceted comment! I don't think I had actually consciously thought of the many sides of Nati!

• Earlier on in the story is going to little parts of everyone's childhoods after the whole murder bloodbath. She and Kraiotan first start training at five. (She is 21 right now, so 16ish years)
• Erion was the spy master for his mother before he was exiled, so he taught both Nati and Kraio "spy games" basically teaching them to lie really well.
• One of her defining features is that she is incredibly self confident/ bordering on vain. Fed by Erion's view that the court are "tittering nobles", she thinks that this is how most noble girls act. So she just makes an exaggeration of her love for the finer things in life.
• The cold exterior is DEFINITELY an act. She is really just trying to keep her cool from smacking Aelina around. I was thinking about the following scene being Nati in her chambers trying to furiously scrub the dirty feeling from her skin. This is not the first time she has killed before, but she is still not a fan.
• I want her to be really motivated towards her cause, but she really does enjoy being a flirt and terrorizing Kraio at every turn.