I say this:
Diaper Lovers are creepy, are they? Well look at all the other kinks around. Spanking, by far the most common and, to a certain extent, accepted, based on a violent tradition of what we'd now term child abuse. The vast numbers of people who read 'Fifty Shades of Grey', about a man who enjoys tying up and abusing a woman. The sexualisation of children in general, with mini-skirts in mini sizes and t-shirts that say 'no money, no honey'. Pole-dancing kits for under tens. The current fashion for removing pubic hair, making a woman look like a 13 year old down below. Fraternity initiation ceremonies. The phrase 'suck it, b****'. Rape porn. Torture porn.
An erotic interest in medicinal underwear doesn't even approach these for twistedness.
Maybe you think we're paedophiles? Not really. I don't see a baby in a diaper and think 'phwoar!'. My interest is entirely confined to adults. If you saw my 'image' collection you'd see what I mean: sexy, voluptuous and fully grown men and women in a certain kind of undergarment.
But that doesn't matter. I feel your real beef is that we are rare. We are alien to you, and difficult to understand. We are a minority. And doesn't the minority always seem to be the one that gets the kicking?
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Or, to condense the above, 'you're a hypocrite and don't know what you're talking about.'