Prude

Okay kiddo, imagine there is a person who gets uncomfortable or doesn't like things that are related to sex or nudity. They might not want to talk about it or see it. This person is called a prude. It's like they want to keep their thoughts and feelings about these things private because it makes them feel uncomfortable. It's okay to be a prude, just like it's okay to be different in other ways too. Everyone is different and that's what makes them special.