Relationships in general make people a bit nervous. Its about trust. Do I trust you enough to go there?
Someone able to carry on a conversation whether the topic is silly or serious. Knowing enough about life so that you always have something to say is a definite bonus.
You can never control who you fall in love with, even when you're in the most sad, confused time of your life. You don't fall in love with people because they're fun. It just happens.