
Its pure pornhwa and recent chapters have changed the genre to NTR.
He is "preparing" her to sleep with other men while he did some "tasters" to test the waters and her response to his schemes (pretending to be massuse to give her a sexual massage without her knowing its him and ordering to answer the door basically half naked and get duped into letting a delivery guy grope and finger her) he has interpreted those "signs" as her ready to initiate her fully into NTR and watching her sleep with men, possibly even go to those gang bang orgies he use to attend. Hes a groomer and a freak.
Keep in mind the FL at this point is suppose to be his "wife".

Not Marquess Chiade. Or the Queen consort.
It was the cowardice of the Emperor.
He knew that both the Empress and princess were innocent yet he still left them to rot in a tower dungeon where eventually they snapped.
The Queen and her brother hating the Empress was expected considering the Emperor did the Queen dirty.

The sequel is just tragic.
Basically the brother who FL ended up with. (basically settled with if we are going to be honest) later cheats on her and falls in love with a "virginal" younger girl who is a violinist. I suspect its because he liked that in his POV this girl didn't have the same "baggage" as the FL does and to her he's the only one in her eyes. Eventually I think he does dump the FL for her. He truly is a piece of shit.
The older brother takes the opportunity to swoop in and start fucking the FL again. He from what I saw in the raws, he basically gives the FL the impression that and he and his wife aren't together anymore and are divorcing (lie).
When she sees a photo of them together as a happy family on social media she realises its not true and breaks down. Also, he is still very much sexually active with his "ex" wife. He too is a piece of shit.
The FL sleeps with her neighbor who seems like a nice guy (as of now) but so far not much progressed for them and she's still single.
It's now hinting in recent chapters her new lover is going to be a High School student which is just a mess.
In the most recent chapters after she confronts the older brother about still being with his wife.
He tries to "explain" things to her. Only for her to flee their meeting upset. I think he tries to chase after her in a car, but his vehicle is in an accident and he is now dead.

Its still ongoing.
Currently the sequel raws are at just after the older brother died in a car accident. Both MC and the younger brother are now mourning over him.
Younger brother basically left the MC prior for a fellow musician (who I think is younget) and Mc's neighbor (whom she has also slept with) is offering to give her "support".
I hope we see a special side story or flashback about the ML's parents. They seem more interesting than the main couple.