So the (evil?) sorceress wants his heart to gain immortality, right? Is she hoping that if she sends him off to some hellish (alien more likely) place he'll fall into despair since he'd not be able to find love? And then when he does..... Actually, I see a lot of potential with the story but you'd want to detail things out more. It's always best to figure out motivations for characters because then the story just writes itself.