PhysicsGirl:

If you can't deal with a particular kink, that's fine. But that doesn't make that kink bad, the person who has it crazy or make it OK for you to make the person feel three inches tall about their sexuality.

You make some good points. First off, we're definitely on the same page about the fact that these kinks don't make people bad or crazy. (My reference to "an extra level of crazy" was not intended to be interpreted as a clinical diagnosis) And I do think it's clear that the LW (letter writer) is reacting childishly and hurtfully. Of course, in terms of kink, everything is relative. But there is a difference between oral sex (which, these days is no longer considered particularly kinky by most people under 60) and Pampers, PVC outfits and whips. These are still commonly viewed as, at the very least, odd.

Leaving aside what is revolting to whom and for what reasons, in this case, we're dealing with what appears to be a compulsion to indulge in an activity that the vast majority of people find ridiculous and humiliating, and the opposite of a turn on, even if it doesn't inspire revulsion.

I don't think all kinks or all kinky people are created equal and I don't want to give the impression that I am in any way intolerant of their right to sex it up however they like. I am saying two things.

1) The fact that folks should be tolerant of kinky folk in general does not mean that they have to be tolerant of this in their chosen partner. Let the kinky folk find other kinky folk and leave the vanilla people alone. The vanilla people are easily traumatized.

2) This particular guy (with this particular kink) is really, in my opinion, a guy with serious issues. I don't doubt that his childish and unnecessarily cruel fiance has a few of her own. Refusal to even discuss this with her boyfriend of four years is certainly evidence of an issue or two on her part.