Odd the repository has "safety" in the name. Are NSFW images considered "unsafe" in some weird way?
Yes, they are considered not safe for work.
You know NSFW means "not safe for work", right? Safety has different meanings in different contexts. There's also a space of advertiser-safe content.
"Safety" as in "trust and safety" or "brand safety."
Safe always implies avoiding a damage; which one is defined case by case.
I've always interpreted the word 'safe' in NSFW as avoiding you to lose your job if caught by your boss.
There's nothing else inherently wrong or unsafe in nudity.
Edit: the author removed it.
Don't see a way to report this on Github.
There's no secrets here, just IP addresses and hostnames, so there's no real security issue. If you want to report it to the author you can try to message them or create an issue.