The built-up to the revenge was so long and painful, I was hoping an entire chapter dedicated to the torture of the Star maiden...
I remember reading at least two novels that went into detail in a similar situation and to be honest it didn't feel good.
One had a concubine who is literally stupid steal the king's affections. She dies a miserable death, and it's so fucking awful that actually makes you feel bad for her, even if you know stupidity past a certain point cannot be forgiven.
The other one had a similar ending to this, with the possessed heroine being sent to 'relieve' the workers, and it ends up with her slowly dying of an STD. It went into a lot of detail of her last moments, and once again, it felt cruel for the sake of cruelty.