I have NO idea why they are called bunnies, and I always kinda imagine a white dead bunny being thrown around, with its fluffy neck all weirdly broken, and a bunch of annoying girls squeeing over its weirdness.
No, seriously. I really have that mental picture. It's really disconcerting.

Prompts are used in any creative writing course/workshop and are actually a fun and useful device to exercise your writing mojo. So, I'm not sure why you want to kill, but you can't kill the bunny. It's very dead already. :P