>>Posh
This is exactly what you do. I got handed "On a Moonless Night" as a prompt once. So I wrote about Trixie stealing everypony' s butts. Because moon -> mooning -> butts.

I will note that I also have a story named "End of a Rainbow" that is also about butts and not a cupcakes ripoff.

What I'm saying is, if you try hard enough, any prompt can be about butts.

Gotta admit, I'm probably not gonna have time due to my job, but hell yeah, I'm gonna actually try.