That's for damned sure as mustard

If I had a nickel for every time I became obsessed with a charming, century's old, undead man with perfect hair and a metric shit-ton of self hatred, who got himself trapped as the servant of an abusive, power hungry tormentor who sent him out to harvest souls to make him more powerful, who meets someone special, is at first cold and aloof then starts a relationship with them in order to manipulate them for his own ends but ends up falling for them, turns out to be a dorky little goofball at heart, and ultimately ends up sacrificing his orginal plan to be free of his torment in favour of helping his love interest and therefore ending the cycle of trauma and abuse to become a better person that he never thought he was capable of - I would have 2 nickels.