Eh, I don't know about this one.
Hero's kind of rapey.
He is 100% rapey, but since the story is trying to go with a medieval setting that's expected and even a natural part of the culture at the time (even if disgusting) that's why the other monster girls are even competing to be in her place (without even touching the age subject that's also another issue) (its why the lamia wasn't respected in her tribes rites but still didn't care)
What could salvage this is if she actually teaches him about love and how to handle people so that he can treat the monster girls with more respect etc etc. if it goes for the shoujo/josei thing of cool douchebag keeps acting like cool douchebag until female just gets into it (which is why i dropped ibarahime) then yeah that would be sad, so i'm praying for a more unique approach