Uuuugh. I wanna spoil u. Hahaha
I've read the novel.
It's because she consumed mugwort so she stopped bleeding, but the same mugwort with some special ingredients that will make her fertile which the dr her husband hates can give. Because that dr wants to keep the monster blood alive , she comes back ones in awhile to make sure an heir is born. Lucia will start want to have a child just like her husband since they will confess with each other. It's a sweet scene cause they were ready to face their feelings and throw the contract. Then, the son will come back and love Lucia like a mom. Her husband gets all jelly with attention that Lucia gives to the son. That son is not his though
where did you read the novel? can you link me pls
I had it in my bookmarks, here: https://rubymaybetranslations.com/table-of-contents/
There are couple of translations, but this one is completed.
A warning for the bashful, the novel is pure smut (but very well written smut )
In the previous chapters she did say on her first period she ate something that made her stop see her period. She knows the cure to fix it but she doesnt want to.
Oh also her situation (eating a plant on her fist period and unable to get pregnant.) is the exact conditions met for her to be pregnant with his child.