Funny. My biggest complaint about the game is Li.
The whole love thing feels forced or added on as an afterthought. It's as if they felt they needed a reason for the player to go and kill the last boss so they added a lover that could be conveniently kidnapped. Call me old-fashioned, but destroying several civilizations is enough of a crime to warrant death penalty already; You don't really need to make it personal.
Li appears, Naija somehow makes him merman, and then he's completely irrelevant to the game till the precise moment he gets captured(the fact that you need him to open doors to Sunken City is just an excuse for forcing the player to have him "in the inventory" after the Mom and Dad boss). One of the first things I did after getting him was to visit the crashed sub in The Veil. He didn't really care. He didn't care about rest of the game, either. He's just blindly following you around and only interaction with him is switching his combat mode on and off. Mechanics-wise, he's exactly like just another pet: minor boost to your combat capabilities.
In fact, that raises some rather disturbing questions. Just what did Naija do to Li? He always follows you or stays where you tell him to. He never speaks(it's true that humans can't speak well underwater, but there's fresh air in the very Li cave so he could simply climb out of the water). Doesn't the guy have any friends or family? Is he last human left alive, just like Naija? If not, I'd imagine him at least letting his mom know he met this mermaid and to not wait with the dinner. As mentioned above, he acts just like a pet, so the only logical conclusion is that Naija lobotomized him when making him merman. You don't know the power of the Dark Side The Verse, indeed.
Then there's the aesthetics. Li's animations are poor(at least compared to Naija's) and because he can't change forms he gets left behind all the time. And while it's easy to accept bosses and aquatic life ignoring your pet, it's much less believable that they would ignore something bigger than Naija attacking them.
So the bottom line is, I feel that the whole love thing hurts the game's back story more than it helps. It would be much simpler to make the recurring theme "civilization x destroyed by Creator", and after visiting all of them Naija realizes that's who is essentially responsible for her loneliness so she kicks his ass(which of course results in unexpected happy end we all know). Don't get me wrong, the game is fantastic, but the story is just hard to swallow, and that's something you need to do every time you play.
On a side note, I read on the Marian site that it will deal with finding love as well and roll my eyes. Dear developers, seriously, you can make a meaningful/"art" game without love themes...