"Okay , turn around and drop your pants" you say, adjusting the settings on the gun.
"Allright..." said your brother, turning and pulling down his pants and underwear to expose his firm muscular behind. You zap one check and then the other, Chris wincing at the sensation. Instantly, his butt began growing in size, as the hair on it receeded away, a nipple popping out of each cheek.
"Oh fuck" said Chris, steadying himself on the door. His ass breasts grew bigger and bigger until they where the size of beachballs, bouncing as they protruded from Chris's backside, sloshing about with milk. When they stopped growing, Chris turned to look at his new butt, sticking out a good few feet behind him, almost falling over.
"This is awesome!" said Chris "shame about my balance though"
"I gotcha..." you say, firing the gun at his firm, bulky pecs. Instantly they start to swell inside his green army shirt, stretching it until it began to rip, as two basketball size breasts burst forth, bouncing and jiggling atop his muscular torso. Chris began to feel them up, teasing the sensitive nipples until milk dribbled forth, his dick rock hard.
You find it hot too, as you reach out and squeeze Chris's butt nipples until they spurted milk too.
"Ahh yeah, that's the stuff" says Chris, smiling in ecstasy.
"you like this huh?" you say grinning.