OK, i know i'm a bit dark and disturbing, but this is something which i've wondered about for some time: might inflation be inherently arousing to the inflatee for physical reasons.
Bear with me on this one please, sorry if this freaks people out, but these are my thoughts. We obviously know that real inflation beyond a certain rather disappointing limit seems to be hard or impossible to achieve without killing someone, though i also think you can probably train your body to accept increasing volumes of gas gradually. If people really can be substantially inflated without killing them, pressure inside their torso will build up and push blood into their extremities and carbon dioxide will build up in that blood and cause blood vessels to widen. Also, their clothes will probably get tighter and rub against certain parts of their anatomy. So you have an extremity becoming engorged with blood, that extremity vasodilating and letting more blood in and then getting rubbed against with tightening fabric. To me, that sounds like it would lead physically to sexual arousal.
Could it therefore be that not just we but almost everyone would be turned on by inflation? Or is this just wishful thinking? If so, what would stop it?
I believe one must make the distinction between stimulation and actual excitement. Enhanced pressure & blood flow on sexual organs and high-sensitivity areas would no doubt stimulate, but I reckon unless the person had an actual fetish for it, other emotions would counteract that (if it's out of the blue, confusion; if forced, probably fear as well).