Girl that transform into futa, or the inverse
>Girl that transform into futa
I believe futanarization is the word you're looking for, OP.
Critiq-d drew it in one of the /d/rawthreads. Here's more of his stuff on the booru:
Reciprocal Corroboration. Here's the non-Sad Panda link:
For the record:
The two girls are named after two of the main characters from Cardcaptor Sakura
Vice - another word for a clamp (Clamp being the group that wrote/drew Cardcaptor Sakura) her opening line is even a variation of the catchphrase of the character Clamps from Futurama.
Man... screw you guys for raising my curiosity.
I came across the original version 3-4 years ago, and I'm the kind of guy that has to know the answer when something pique my interest or it'll bug me forever.
I had to scroll through 20-30 pages of some anthology books based on artstyle, then had to translate the author's name in kanjis based on stroke numbers to get this information.
The artist name is Fujinomiya Yuu.
The book that this oneshot belongs to is Futanarikko Pretty Vol.01.
And because I'm such a nice guy I'll just post the link right here: http://exhentai.org/g/29046/7679d6a031/
The page you are looking for is 157.
Next time you rewrite the dialogues don't put your credit over the name of the artist -_- Coulda saved me 20 mins.
[Porika] Iyarashii Kuni no Alice 1 (Alice in Wonderland) [English]
[Porika] Iyarashii Kuni no Alice 2 (Alice in Wonderland) [English]
Probably porika's best works that is available on the internet