apparently he ends up getting dating advice from mc lol. So he starts like... Actually seeing her as a person bc they spend time together to do that. (also I think the redemption arc is bc the Prince is super selfish and violent towards anyone who isn't ariel, so like in the og story, he plotted to get rid of anyone who was close or friendly to ariel, got them to get rid of rivals, etc. Super scummy manipulative stuff )
And then eventually is like "that's mine that is" when it concerns mc, so he's no longer hostile towards her and is actually treating her like a sibling.