There is only one file type that uses the .NOP extension:
WangReal Engine Game Data Archive
An NOP file is an archive used by White Day: A Labyrinth Named School, a Korean survival horror game. It contains data files for the game, which include animations, textures, meshes, and transitions. NOP files are compressed to reduce the amount of space taken up by game assets.
You will most likely only encounter an NOP file if you play White Day: A Labyrinth Named School and are looking to modify assets in the game. However, NOP files may be packaged with other games that use the WangReal Engine. NOP files can be found in the directory that the game is installed.
|Sonnori White Day: A Labyrinth Named School||Paid|
Updated: October 21, 2018