Drool. I hate the word drool. It's so inelegant. I read a study once, that took people unfamiliar with various languages and read them assorted words. Even without understanding the language, most people attributed negative connotations to negative words. In short, negative words just sound bad. Drool just sounds bad. The 'dr' sound has a harshness to it, and there are no good words with a double 'o' in them. The very sound has sort of a primal trait to it, a throwback to barbarianism. I would prefer the term 'saliva', because it sounds better, and I used to listen to a band called 'Saliva' in high school, until I lost the CD. (For any kids out there, a 'CD' is a shiny disc that people used to use to listen to music. You would put the disc into a large box called a 'CD player', that would then play back the music. You had to take care while moving, since the slightest shock to the CD player would cause the disc to skip several seconds of the song. And I've gone way too far afield.)
Also, there is the bond. The best romance shows are the one that don't have an artificial bond between the characters. So why do so many shows have these then? Well, let us journey into the brain of the otaku. Your garden-variety otaku is completely lacking in self-confidence when it comes to the fairer sex. So characters based otaku have to have some sort of non-romantic bond that ties them together, so the romance can bloom. This is especially pronounced in incest and lolicon shows, where there bonds are family or dependence. This is very prevalent in male-oriented shows, as female romances tend to show more realistic romances. The former emphasizes dominance, the latter a meeting of equals. This show is a little weird in that the bond is in the opposite direction—the dude is totally dependent on the girl. But it still weakens the show.
And finally, this is a high risk, low reward show. Even if show manages to transcend the tangled thorns implied by its premise, it will always be held down by just how nasty that premise is. And the odds of that happening are very low. This is Astarotte's Law: No matter how much a show seems to improve over its premise, it is still devised by the same guy that made the premise, and as such, will regress to those levels before the end. In other words, this is show about drinking a girl's drool, and it will return to what you would expect of a show about drinking a girl's drool by the end of the run.
But you know what? I'm still going to watch it. There's just something about this show I like, despite its best efforts to repulse me.