Another story search

Lurker Here :) Hi All

It's been awhile since I read it, but something reminded me of a story I read, and I've been trying to track down a copy of it.

The gist is a set of "magic" underwear, panties/bra. One scene, relatively short. Friend A gives a set to Friend B. This friend puts them on, and finds herself getting turned on. As she gets more turned on, she grows faster.

Friend A feigns ignorance, then offers to help Friend B take off the panties/bra. Friend B thinks better off it, and then proceed to taunt Friend A, who then grows, fearing explosion, until the panties/bra tear. All according to Friend B's plan.

I have no remembrance of the title or author, so I think there's probably not much hope that it'll turn up, but I figured I would try a story search post.