@Myong has stood a good point. However, when I used to quest convert, I got this all the time simply because the texture quality was too low. Try upping the texture quality to the next ones above it and see if this fixes your issue!
Thats Ciel and you can find both SFW and NSFW versions here https://forum.ripper.store/topic/16683/lf-シィル-ciel-found?page=1
Flat chest version of the model is here https://forum.ripper.store/post/454315
i personally used filecr for sp 10 and pb for photoshop, but you can also download the trial and run this to clean it yourself https://github.com/wangzhenjjcn/AdobeGenp/releases
@Lokote2134 You go to mats or materials go to textures pr type in textures in the search and press control "a" then go to the compression section and lower it and press apply