So do you know what exactly the model was trained on? Unless I missed it, there's no training code in the repo, or any other indication of how data was prepared.
I'm not sure. I suggested Danbooru2017, as I mentioned, and I thought he was using it, but double-checking his Reddit comments he seems to imply he's using a custom private dataset only at this point. Maybe he hand-extracted a lot of censored/original pairs from various places.