The medical plasma packs in the game have always annoyed me for one reason: they can only be purchased, not harvested (unless you have Cats and Dogs).

I've always loved the creepier vampire socials, especially when playing Vlad - I feel like his main greeting to humans would be 'nice neck!'. So I unlocked the socials that u can only access when your thirst is low. They're filed under the Vampires pie menu.