Kind of have a fairy tale/medieval times like idea in mind with Denmark and Norway (well TECHNICALLY it could be USUK, but I don't like them as much).
Sketchy on the details, but the main one is that Denmark goes to Norway who is a seller of spells and small magics and asks for a love spell. Now then, love spells are tricky/dangerous/rare/expensive (whatever you want), so Norway essentially takes Denmark on as an apprentice (slave) to gather ingredients and things he needs for Denmark's spell and many others. You can see them getting closer over time (maybe), and then Norway tells him there's one more thing needed for his love spell (I lik