You found the red flared pants in the back of a thrift store that may or may not have existed the day before. They felt unusually warm when you picked them up. In the changing room they slid on with unnatural ease, molding exactly to your body no matter your original size.

The moment the waistband settled fully against your skin, soft living fibers sank into your hips, ass, and thighs—not painfully, just completely. A deep, pleasant heat spread through your lower body. Then the expansion began: slow, steady, and thorough. Your hips pushed outward, your thighs thickened, and your ass grew heavier and rounder, reshaping you into a pronounced hourglass silhouette. The flared red fabric stretched with you the entire time, never tearing, never loosening.

The pants can still be removed and your body going back to normal... for now. But if you reach climax while wearing them, the fusion will become permanent. The expansion will lock in forever, and the distinctive red flared pants will remain sealed to your bottom for the rest of your life.