
The main problem proposed by the author for the protagonist is if she should cure her infertility and get pregnant or not. That is such a shallow and misogynistic way of writing a female character...
Also, she as a protagonist has nothing to relate about... she has absolutely no bright features and barely a personality...

No. The fertility problem is less of a problem for the MC than it is for the ML. To others, her fertility is the most troubling thing in the marriage and relationship. To her, it’s just another stick to carry. The fertility thing to her is like a defensive state just in case. It allowed her the marriage as a condition and a second escape route just in case she meets a man who harms her. (No one wants to have a child with a scum; the child is definitely innocent but the scum definitely isn’t. So no child is better). The actual problem throughout the story is the ML trying to win her love with the constant reminder of the contract. And the MC with her trust issues and her constant fear of the past.
If you view it in a misogynistic way, then the MC is relying on the love of a man to succeed in her escape from her past.
In a lesser fierce way, it is a story where the MC learns to love and trust once more filled with throws of love from the ML.

V.pix said it perfectly, but I want to add that her infertility is more equivalent to taking the pill then anything and also goes in a very different direction then you would expect. Also about her personality, I can kind of see were you are coming from. In the books she had such an amazing and strong personality that you really got to see develop over time, but the this is not capturing as well and I think it might be the lack of internal Monolog compared to the book. I hope it gets better.
Horikoshi don’t you dare to lay a finger on the only decent father figure in this series (╯°Д °)╯╧╧