Alongside the uncensor patch, Steam user Shisen has also created a mod which changes character appearance in 'battle mode', in order to reduce breast size to a more reasonable stature. This mod can be downloaded here, and to install it just continue following the patch install instructions!
When your older sister shows you how to do naughty things in the intro, there's accompanying imagery.
Patch download: https://mega.nz/file/tDAjBAgC#Vg16dqH9NnhN7cmqvbLzorLv3k7mSy9r0fWU9zGuayo
Steam store: https://store.steampowered.com/app/726990
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