The answer takes him aback. Malcolm had assumed that she was young, but not that young. In a way it makes sense, based on their previous conversations and how Malcolm feels like she's been 'protected' from the world her whole life.
Regardless, he'd feel like kind of a creep asking her to dance. Abigail probably thinks someone in their thirties is a dinosaur.
"Definitely," he replies with a smile. "I didn't go to many parties though when I was eighteen. My social life was kind of non-existent." It's still non-existent. "At least I met some people in college who genuinely seemed to like me."