On the topic of advances, defined as actions that move an interaction from a more neutral state to one where sex becomes a factor, I wrote this some time ago:

While some actions — i.e., asking for date (sometimes) through exposing oneself (always) — are clearly advances, the question of what constitutes an advance is really up to the target of that message, and that complicates matters greatly. I recently inadvertently put the brakes on a developing friendship just by using a heart emoji in a text message. The recipient of that message had a history that included sexual abuse by a coach when she was younger. While my intention was just to express happiness at our impending meeting, to her it was a glaring red flag and constituted an unwanted advance, one that probably caused her a great deal of pain, and that in turn caused me pain.