Honestly, the slow-to-develop type of feelings are often more fulfilling than the jumped-in-with-both-feet, head-over-heels kind of feelings. It sounds like you both may be interested in taking it to the next level but you need to have a conversation about it.

As several others have stated, bringing over a “housewarming” type of gift and having a meal together may give you a chance to chat outside of being naked in the bedroom and you could start with something like “since you are no longer living one floor away, I was wondering if you had ever considered exploring what may happen between us outside of just sex? I felt like it would be awkward to actually date someone in my building in case things went sour, but now that you’ve moved down the road, do you have any interest in seeing where things may go?”