Sam wrote about this in his recent blog post, but I've found that important and seemingly obvious things often bear repeating. So with Demo Day approaching, I'd like to make the following point explicit:
Y Combinator has a zero tolerance policy for inappropriate sexual or romantic behavior from investors toward founders.
Don't even think about doing it. I will find out. Y Combinator will not continue to work with you.
News also travels fast around the YC community. Past and future YC alumni will likely find out about your actions and find them equally unacceptable.
Nearly all the investors we know are completely upstanding and professional, but even one inappropriate incident is too many.