In MOST cases, propositioning a coworker is harassment. Propositioning them twice is unmistakable harassment, and has already gotten out of hand. You’re at work to work, not hook up — and not to hook up with people who are at work to work.
I’m not surprised that people still feel the need to ask this question. But it’s exasperating nonetheless. It reminds me of a little kid convinced that if they ask three more times they will get that cookie. Even though they’ve already been told ‘no.’