A (2) Girl is a person (often a female) that just repeats a line that you said back to you. A reason has yet to be found why people are sometimes like this, it is believed that they become this way due to their lack of creativity in communicating with someone. A person like this is often found when chatting online, especially when you're having a flirty conversation.
Ex 1;
Boy: I want you so bad. I'll make you the happiest girl in the entire universe.
Girl: I want you too so bad, and I'll also make you the happiest boy in the entire universe.
Boy: What a (2) Girl.
Ex 2;
Boy: I'm going to make you the queen of my world.
Girl: Same.
Boy: What a (2) Girl.
Ex 3;
Boy: You are the bread to my butter.
Girl: (2)
Boy: What a (2) Girl.