Is that possible to delete some of cg in the game?
What do you mean? Like from the gallery??? Or from the game's files in general?
Yes to both- but I'm going to assume you mean from the Gallery.
I'm sure there is a more surgical way to do it- but you can delete everything by doing a full deletion of the SoC folder in
C:\Users\
Username\AppData\Roaming\RenPy\seeds_of_chaos
Just replace "C" with whatever drive you have the folder in and "Username" with your computer's username.
For Example: D:\Users\monk_56\AppData\Roaming\RenPy\seeds_of_chaos
Do note that doing this deletes your save games and other CG unlocks as well. Perhaps deleting the "persistent" file in the folder will delete your unlocked CGs without killing your saves. You could also just drag the saves you want out of the folder before you delete it and throw them back in after you do. Not sure- haven't fussed around with it myself. There are likely ways to delete specific CGs from the gallery- but they are probablly fussier than just doing another playthough to unlock what you want after doing a total purge.
Pathing is similar if you have the program as a steam game- though I don't remember the specifics.