From what is arguably the villainess manhwa with the most convoluted premise, Behind His Kind Mask, in which the protagonist is a cross-dressing stalker notiviate obsessed with the heroic pope, who turns out to be a bloodthirsty Machiavellian asshole. She creates a magical mutually assured destruction pact by kissing him? Or something? Where if one of them is injured or dies, the other also does.
Anyway so far most of the story is actually concerned with magical animal husbandry.