I made a dirty joke to a woman at my workplace after hours. There were 3 of us (two girls, and me), and some bystanders at around 11 PM, one of the girls asked me if I had a bicycle, I grinned and said "Why, do you want to be the second one?" and there was a brief silence, after which I said "nevermind, that was stupid... but yeah, I do etc." (she wanted to use it) The woman in question is engaged but still seems pretty flirty to me. Didn't seem to be a problem in the immediate term but if I keep piling up these sexual remarks I don't want to be accused of "harassment" or be a nuisance to my colleagues. What should I do and what should I do in the future?