The ML should be Jeffrey. It will be disappointing if it's the demon king. What's up with MCs going for the dark, mysterious guy when you have a supporting and loving guy all these years. In this case, Jeffrey and Charlotte have known each other for 100+ years. Who the f cares about the demon king who suddenly shows up again with yandere vibes. Authors should move on from the bad-guy-turned-good-gets-the-MC trope.