Katie sat there, unable to move, watching transfixed as her best friend continued to pleasure herself on the bed. Her stomach ached, the desire to approach her friend and help her achieve climax, possibly for the last time ever was reaching fever pitch, but a barrier of common sense held her back - what if just touching the liquid affected her in the same way, causing her to collapse in a pile of lust, masturbating away her sex?
She crossed her legs, the moistness spreading inside her panties.
Tiffany, again realising the feeling was dissipating sat up, propped herself up with one arm. Spreading her legs wide, she proceeded to vigorously fan her ever-diminishing sex faster and faster.
As her final climax built to almost titanic proportions, she started to eject the bottled liquid from her now micro-vag along with ejaculate from her almost pinhole urethra, the pressure build-up causing it to spray everywhere in jets. Finally, she had reached the peak of her mountain and she collapsed in a wet pile on the bed.
Katie, flushed red and *really* in need of her own release by now, carefully removed herself from the chair and approached her prostrate friend. Slight pants emanating from her as small orgasmic aftershocks flowed through her body, but when Katie got a good view of Tiffany's crotch, she gasped.
Where previously was a healthy girls sex, there was now... pretty much nothing. The central skin texture was different, sort of like fresh scar tissue, but small flaps of skin (what remained of her vagina lips) fell vestigially at each side. A noticeable welt was visible on top, presumable where her clitoris once was.
Unsure what to do, Katie turned around to think about what she had just witnessed. Whilst standing up, without realising it, she had brushed her hand through some liquid substance on the bed...