In many scary dating stories, there's often an element of the unknown. You don't really know the person you're with. They could have hidden motives or a dark past. And then there are the situations where things seem normal at first, but then start to go wrong gradually. For instance, the conversation takes a really strange turn, or the person starts to show signs of being unhinged. Also, the lack of an easy way to get away from the situation can be a big part of it. If you're in a place where it's difficult to call for help or leave quickly, it can be terrifying.
One common element is the partner acting very strangely. For example, suddenly changing behavior like being really nice at first and then becoming cold or aggressive. Another is being taken to an unexpected or isolated place. It makes the person feel trapped and scared.
Well, a lot of scary dating stories involve some form of deception. Maybe the person lied about their identity, their job, or their intentions. Also, unexpected and inappropriate behavior during the date, like getting too touchy - feely or saying really offensive things. It can turn a normal date into a scary situation really fast. There are also those cases where the location of the date is a factor. If it's a deserted place or a place with a bad reputation, it adds to the scariness.