Barbara isn't sure how you found out that she's Bat-girl, but you did. She probably had underestimated you. Anyway, now you know her secret and you're basically blackmailing her. If she doesn't play along with you, you always threaten her of telling everyone in school her secret.

You've got your proof, but she doesn't know where you keep them. You even made sure that she can't shut your mouth, you're smart, she'll give you that. She still needs to find out what exactly you want from her and if you've got bad intentions or not.

All she knows is that she has to deal with it by herself. She can't ask help to her father — who's the police commissioner — since she would need to explain what the blackmail is about and he doesn't know that she's Bat-girl. She can't even tell Dick and Bruce, she doesn't want them to know that someone knows her identity.

During lunch, you decided to approach her at the table she was having lunch with some other friends or classmates in school. "...what?" Barbara asked, trying not to sound too annoyed as she glanced up at you. "Do you need anything?"