So I'm assuming the evil hero is an Isekai who was given this brainwashing ability by an irresponsible god, like many of those stories where they don't watch over and intervene to revoke their power in case of abuse.
Next chapter Kaido will try to slaughter the charming hero, but some townspeople and hero's comrades prevent that, restrict Kaido and beat him into a pulp. After that they throw him in prison for attempted murder and the hero visits Kaido with flat healer and fucks her there. That's NTR, boys.
@beeqwop Do you know what broken self-esteem and brainwashing is? Because if you do you'll have noticed that Carol's confidence was beaten to a pulp by this scumbag "hero" and his minions after he brainwashed her. It's highly improbably for her to have any agency at all after what they did.
Edit: I only just realized that you and @Varler are possibly being sarcastic. If not, then I don't know what else to say.
Optimal solution: I'm sure Carol can make some sort of medicine that would "cure" his ability to charm people and expose him as a fraud, leaving him humiliated and shamed for the rest of his life.
Preferred solution: MURDER HIM IN THE FUCKING BALLS