Unlike the suave Sirius and the social lite James, Peter was scared shitless when it came to girls except for Lily. Not saying that Lily wasn't a girl because she was very female, but she was also a friend of his that helped him out and he was always on the off limits list because James liked her so darn much. That made it just easier to be around her. But back to why girls made Peter run to the hills. They just made him nervous, when he was nervous he tends to be clumsy, when he's clumsy he gets kicked out of stores, classrooms, or just embarrasses himself to death so bottom line. No girls even though they're really really pretty and soft...
"Chocolate sounds good," he mumbled looking around not really paying much attention.