[Toruneko(獲る猫)] Konna Mune Demo Ai Saretai! (こんな胸でも愛されたい！)[2014-09-10]
from:
[Toruneko(獲る猫)] Anoko to Iikoto (アノコトイイコト)[2014-09-10]
Code:
https://www.sendspace.com/file/2krxtu
No actual process, natural growth in a span of days/weeks apparently, she was initially using padding.