When my LTR and I first had sex, just before we went to the bedroom she asked "Do you want to?" I of course said yes and we enjoyed the rest of our night.

Now over a year later, that question has kind of become our way of initiating sex. We'll make out for a while and then I ask "do you want to" and then we go. It's not that I'm actually asking if I can have sex with her, it's just how it came to be. I've been lurking/reading here for a couple months and now it feels weird asking "Do you want to?". It feels weak, but I can't think of an alternative to move things along.

So my question is, how do I move us to the bedroom without asking to have sex, and without sounding overly forceful?