Here is a simple tutorial on how to get the 18+ patch. this tutorial also teaches you how to install this patch.
Download after buying
Now wait a few min for it to download
Instal
after downloading make sure both files are in the same map
now press part 1
now press part 1
Now you will get this screem press the first (blue) button
this will start making a map called vol4_steamR18DLC
now open that make and you will find a file called nekopara_vol4_Steam_R18DLC
click it and it and press next 2 times till you see this
make sure the destination folder is correct
example: e:\steam\steamapps\common\NEKOPARA Vol. 4\
afther istaling you will get this
corectly instaled
if instaled correctly you will see this when starting the game and in option menu
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