Muscles for Christmas

"This year, give the woman in your life the gift of muscles!"

Recently-engaged Don invites his sister Grace to his home for Christmas, but the formerly skinny young woman has become as muscular as a linebacker and as strong as an ox! Grace's strength doesn't come just from lifting weights, though, because she's discovered an ancient relic that can transform any woman into a muscular amazon in just minutes, and the stocking-stuffer she's giving her girlfriends is turning them into sleeve-stretching muscle girls –– including her future sister-in-law! Can an ordinary guy like Don handle it when his sister, fiancee, and even female co-workers become suddenly-jacked and incredibly strong?

This story contains female muscle growth, amazon transformation, mixed arm wrestling, women outmuscling men, and a bit of male shrinking. It occurs in the same universe as classic female muscle growth story "The Amazon Artifact", but is not a direct sequel.