Katie was in time to view Tiffany's 'problem' developing. Her friends crotch was seemingly bubbling under her silk panties.
Then, catching Katie unawares, a penis erupted from above her vagina, presenting itself over her panties. Moments later, a second penis pushed itself around the side of them, followed by a third around the other side.
Katie reached in and pulled her friends panties down, just in time to release a fourth penis.
There was no rhyme nor reason to the growth - the first penis grew from above her sex, as if it were a real man's penis. The second grew out of the right side of her labia, quite uncomfortably. The third and fourth came from inside her vagina, seemingly rooted together.
As she watched, Tiffany's clitoris pushed out, extending to the same length as her new organs before changing in shape to form a fifth penis.
Tiffany stirred and opened her eyes, sitting up bolt right, unaware of her 'change'. "What the hell Katie, why are you staring at my... what the fuck..." exclaimed Tiffany, seconds before a sixth penis emerged from the root of the first. "WHAT'S HAPPENING TO ME"!
"Calm down Tiff" offered Katie "It's clearly that formula you took. Why the HELL did you drink the whole lot?"
"I don't know..." answered Tiffany, wincing as a seventh penis pushed out from the bunch of new organs she was brandishing. "...I guess I just wanted to teach you not to be, err, so cautious about things".
"You idiot" snapped Katie, quickly croutching down to hold her friend as what she assumed as number eight started to emerge.
"I think it's stopping..." said Tiffany, breathless.
"Can you stand" said Katie, reassuringly. "I think so..." replied Tiffany.
Once she was up, Katie escorted Tiffany slowly to a mirror so they could view the damage, the afflicted girl barely able to walk through tiredness and uncomfortableness. Eight penises, hanging from her crotch like some strange octopus. Each penis was between 6 & 8 inches long.
Tiffany cried, as Katie comforted her.