The world is now as if Pokemon have always been there, but no major changes to history have been made otherwise. But, for some undetailed reason, you are forced to marry one, and if you don't, you'll be killed for once more undetailed reasons. You are given free choice over which one, however, you are not allowed to be apart from them for longer than a day straight, and you aren't allowed to keep them inside a Poke Ball. Assuming you have the food and supplies needed, they can take care of themselves just fine, but still need attention like anyone does from another person. And you'll be stuck with them till death do you part.
So, which Pokemon do you pick? How will you cope with the situation?