Just an idea I had - list how inflation crosses into your other fetishes and why.
My personal examples:
Latex: tight, shiny, balloons are made of it, it stretches
BDSM: forced inflation, pushing limits, bondage (immobilisation)
BBWs: Duh, figure it out :P
Big breasts: see above
Too-tight clothes: again, easy to understand
Messy sex (oil, cream, cum etc): result of popping
Let's see what else people come up with :)