Why, of course. What else would you do with it? If the story is not good (and this is almost always the case), what's the point?
I just don't find the "Let's have sex first and talk later" appealing. And it's not unique at all. I've seen characters introduced and put into sexual situations in five minutes time and time again. Particularly, in games where dev is totally incompetent as a writer, which, don't take me wrong, is not JOHN's case, but for me it's simply not enough if I can't get myself to care about any of the characters.
Whatever floats your boat, mate.