Responses
Actually, the grandfather was the one who inflicted problems for the prince and he was the lead wizard or something. And our FL hasn't read the entire book so she doesn't know that our ML even when he ends with the red head later finds out that she is the wizard's daughter and the necklace is something made so the prince can't harm his granddaughter. He kills the red head in the end of the original book.

spoilers
so based on what i saw from the raws (so this isn’t for sure just based on what i saw) in the novel the FL didn’t read the book so it was too late since she already interacted w him, n e ways what she saw in the book was that the red hair girl told him why he couldn’t read her thoughts or where she got her necklace which of course from what we heard was from her grandfather and i guess the ML had some trauma w the grandfather or he hated magic idk anyways he kinda goes crazy and kills the red haired girl sooo..