There's nothing to talk about with a 19 year old. Even if you're thinking with your dikk as the primary motivation, you still have to work your way to that point with her. It's just not worth the headache. The other thing is, 19 years olds, look like 19 year olds, and when you reach a certain age they look different. I don't even look at college women the same any more. They just don't do anything for me. Conversation wise, even less.
I'm 37 and agree with all of the above. They look like "young ladies" to me. Kids basically.