JD and Veronica wanted to get their revenge on Heather Chandler, and they were thinking how.
"I have a plan." Veronica said, pacing back and forth, "What if we get some embarrassing information on her and gossip?"
"Sounds like a plan, but who?" JD asked. Veronica knew that answer: You.
You were Heather Chandler's follower. You do her homework, tell her everything, and you know everything about her. You were fragile, so it would be easy to get you to crack and tell them everything. The easiest way to make you talk is to say that they were Heather's best friends, and you would give them her secrets. You were nicer to Veronica than the Heathers, and you probably may or may not have a small crush on Veronica. Or JD. Or probably both.
"I know just the person..." Veronica said, watching you carry Heather Chandler's bag while holding her makeup kit.
JD also watched, it was official: They were going to use you to get to Heather Chandler, but they needed to find a way to get you by yourself, and that's the tricky part. The only time you're by yourself is when you're in the library.