Meet and greet You probably meet at a world meeting – he still goes occasionally, if only because West makes him sit in councils he can't attend himself. The countries have their own rooms, and those hotels have room service and probably even special suites made especially for the wants of those nations. America gets a mini fridge with hamburgers, England a nice tea collection, Austria a piano, etc. Their room keepers are hand-picked as well – they at least have to speak their language, and at best even have a similar cultural background, to make sure they get along. And you'd be one of those housekeepers.

Insert flirty opening line If you're his type, he'd probably hit on you with one line or two. He isn't as bad as France with flirting, but he's still overconfident, with a huge ego and a playboy attitude. If you flirt back, he is going to grin at you, but he's not really going to do anything. West would kill him if he tried anything on a staff member during a meeting.

One step at a time The real connection would come over time. A little smile at seeing you await his arrival at the next meeting, a reassuring sentence after a meeting goes the wrong way, an inside joke before you wish him a good night – that's what would help you two click over time. He'd find himself looking forward to seeing you again, and you'd find yourself placing his favourite flowers on the pillow. He'd start to bring you little presents, and eventually invite you to stay for the evening. You two would sit in front of the fireplace, drink and talk about everything and nothing, and it would be way past the end of your shift when you'd leave his room eventually, smiling on the way home.

Note: While dating a human is always difficult for a country, it's not unheard of. And Prussia knows what he's doing. He has loved and lost multiple humans in his life, and is actually one of the more experienced nations when it comes to dating humans. And when he finally asks you out officially, he will be very sincere about it. For all that he can be an absolute idiot, he is rather careful about his heart.

Old traditions Prussia is actually a nice guest to host as a housekeeper – unlike some other countries that wreak havoc on their suites. Actually, when it comes to cleaning, you'd have little to nothing to do. Prussia, despite his punk rock demeanour, is really tidy. He makes his own bed, folds his own towels, cleans up after himself. In fact, you'd probably have to stop him from taking the new sheets from your hands and doing the job himself. But at least that gives you more time to flirt.

Compromises After officially becoming a couple, things would start to be a bit difficult for you. A nation's s/o is always a bit of a security risk for spilling national secrets. In your case, at least Prussia is not an active country anymore, but still Prussia would probably want you to move in with him. You could probably not keep on working as a housekeeper in the conference hotels, because other nations could try and talk you up to get said national secrets from you. But believe me, if you move in with Prussia, and therefore also with West, Italy will make enough messes to keep you busy.