"Oh my," Sarah beamed at the sight of John, now effectively a throbbing hard-on with a miniature man attached. Although he was desperate to release the pressure in his still-regular-sized balls, Sarah's magic meant that he couldn't until she gave her blessing. Which was pretty much what brought the smile to her face.
"Poor little baby," she teased, crawling over to the fleshy mass on all fours and gently licking John's shaft. She felt the bright red dick begin to flop like a fish, desperate to climax.
"Oh wait," said Sarah, leaping to her feet. "I've got just the thing for this!"
John felt an eternity in the moment it took for Sarah to return from the other room with, to John's horror, Karen. Her own state matched John's: she had been miniaturized except for her vagina and breasts. The latter served to hold Karen down on her back as Sarah placed her on the floor next to John.
"Such a pretty little cunt you have," Sarah teased, licking her finger and rubbing it against the edge of Karen's vaginal lips.
"Please," Karen screamed.
"You're a virgin, aren't you?" smiled Sarah, as she rubbed just inside Karen.
Sobbing, Karen nodded.
"Not for long," cackled Sarah as she grabbed John by the cock and, seemingly against all laws of physics, slammed his full eight inches inside Karen.
Karen's eyes went wide as utter exhilaration tore through her and her whole body erupted into convulsions of pure pleases.
"Okay Johnny boy," Sarah beamed at the miniature fuckball, "You can come now."