Originally Posted by Balls
This is what I have encountered as well. You have to choose the romantic options, for them to take place, in my multiple playthroughs.

obviously you have to choose the romantic options for the actual romantic cinematics to take place.
but if you simply choose friendly options throughout the playthrough and happen to have enough approval, any/all of the companions all of a sudden come on to you during the same night.
There are very few flirting/hinting at romance dialogue options before that night, so it comes as a shock and ruins immersion/the relationships you thought you were building with the companions