I highly doubt it's a nude filter, particularly given the source indicates the artist has depicted the characters appearing in this state (although not this exact combo). It's much more likely that the source isn't the actual source for this specific image, given the image here is higher resolution and depicts elements only previewed at the source (for example the mother being shown with pubic hair is only shown in a smaller image at the end with other sample images).
If you take a look at the text of the source, the artist provides a PSD with 80 layers which can be messed around with like one of those old dress-up flash games.
If you take a look at the text of the source, the artist provides a PSD with 80 layers which can be messed around with like one of those old dress-up flash games.
I feel a bit dumb for forgetting PSD is a Photoshop file. Not really sure how to handle that sort of thing from a Danbooru perspective; that's a massive number of permutations that could be uploaded and not technically be by the artist (and thus weird to source), though I've never been a fan of image sets that stay essentially exactly the same and change a small portion each "page" either.