Blues: Hey -- I gotta go in a sec, but I need a female opinion on something. You *are* a girl, aren't you? (neg)
HB: Lol yeah duh
Blues: Alright, just checking

You can never be too sure. Anyway, here's the deal: there's this junior girl -- we'll call her Pippi, just because I've always wanted to meet a girl named Pippi -- in my class and she keeps implying that she wants to go out with me. Now Pippi is definitely pretty hot, but I'm just not at the point where I want to have a relationship. (DHV) How would you tell a girl that you're just not interested right now?
HB: blah blah (I got "well right now I'm just not ready for a relationship you're a great person though")
Blues: Alright thanks. Sorry babe, but right now I'm just not ready for a relationship -- you're a great person though!

(Whatever advice they gave you throw it back at them) (neg)
HB: Hahaha!
From there you'll want to follow up with something else right away -- as with most negs you don't want to let her respond and change threads immediately.
Tested it today and got great results. Let me know what you guys think -- you can adapt it however you wish. I'm in high school, so you'll definitely want to change the part where you say she's a junior. Pedophilia is definitely a DLV, lol!
-Blues