Responses
The grandfather hates the FL, thats why he made the arrange marriage for the mother instead of her.
you will see just how badly fl is treated and disliked by her grand father in the latest chapters. Her grandfather evens scolds the FL for not referring to the stepfather as "dad"
The author can just make her grandfather had an arrange marriage for her, have her being adult, and the guy have freaky/kinky/pet names or something. But no, the author ended up making more trash storyline cause that’s what they like. Raping and incest bullshit.