Well, you do you then.
As warped as it is, you seem to have made up your mind as too what my motives were, and for some reason claim to know who I am based on a few words.
I don't know who you are. i just get the impression that you're rather foolish in your thinking. But, if we didn't have people like you, we wouldn't know what normal was.
Besides, when you actually think about it, the island is on another world, with values that are their own.
AND, the human MC is actively rejecting the advances about marriage.
There is nothing more here than a culture with different values, and an MC sticking to his own.
You may not see this I guess, since that depth of thought seems to be beyond your capabilities.
Some manga can be truly offensive, I agree. But this is not one of them.
For a young looking character to keep on declaring themself wife and calling him husband. Just....nope. If you even say shit like it's legal loli, that's just disgusting.