In the end the only one he truly despised was the princess.
He has been manipulative with the others in order to exploit them for his goals, but they got their benefits from him as well.
Revenge boner hero chose girl over revenge!?
Keyaru has grown!
But yeah, he had to sacrifice the only girl he didn't brainwashed to get her love (gaslighting her a lot yes, but he didn't use neither aphrodisiac or brainwashing on her)