Here is the full list of all 13 NEKOPARA Extra achievements. It takes around 0-1 hour to unlock all of the achievements on Windows.
Good Morning
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Petted Chocola
Petted Vanilla
Petted Shigure
Petted Maple
Petted Azuki
Petted Coconut
Petted Cinnamon
Boing Boing
Merry Christmas!