Ugh, even if that wasn't her mother, this so fucked up. This is Beatrice all over again.
Btw, I can't believe his men claimed they couldn't find the princess anywhere whereas our MC wasn't even trying to hide. Her maids had to literally drag her. He or any of his men just conveniently didn't see or hear them. I know they were looking for her sister, but since the ML said they could send a replacement I'm pretty sure they would've just taken her instead if they'd found her.