Erotica writer needed for fetish specific short story

I need an erotic inflation/shrinking-man story written based on the following premise: Vain, mean rich couple get lost on deep uncharted jungle tour. They end up discovering a race of tiny two foot tall people who they use their height advantage to abuse. The tribal witch doctor is called in to deal with the threat. Woman is immobilized by being plumped with magic till she's just a quivering pile of booty, belly and titties. Man is approached by witch doctor's big breasted randy MILF wife who tries to seduce him much to his amusement but after he spurns her ends up shrinking him with shrinking powder to half her height and forced him into sex. The couple end up little more than sex objects to the jungle tribe. It needs to be at least 20 pages, thanks!