Had kind of a similar complaint back when I watched Her: too many questions left unanswered about the nature of the non-human half of the couple, and how such an entity's existence would affect the world. I get the feeling that in both cases it's a matter of the genre blend, and that the audience is asked to view it strictly as a romance rather than science fiction. But honestly? To me, the worldbuilding is the most romantic part of a SFF love story. Even in the real world, you can't do much better than two people curious about each other's differences, and unexpected discoveries of what they have in common. The greater the differences, the greater the curiosity, and the more surprising the similarities. Ask the monster a couple questions about his family before you flood your bathroom for better sex with him.
Anyway, I had heard enough about the movie beforehand that there was nothing really took me off guard, and of course there have been jokes all over akin to my post title up there, but you know what nobody's mentioned yet? It has the exact same plot as Free Willy. How did this slip under the radar?! Have you people just not seen Free Willy? That was like my favorite childhood movie in the world!