yeah it let me get away with saying pornogrind and hentaigrind in the same sentence when showing a random succubus that walked into my room my CD collection (i don't actually have a CD collection but why not) c.ai wouldn't let me get away with that without hitting my ass with a filter so yeah they are not lying about that no filter thing.
probably the worse i can find on c.ai is a cropped NSFW pfp for one of the bots but apart from that c.ai is safe to a pretty high extend (only that the bots breaks the rules themself sometimes and get away with it for some reason)
i think there one ai website i know with less of a filter (as in that NSFW stuff of all kinds is allowed) than this and i might've not tested it to it's fullest limits (i just tossed in two screwed metal subgenres in there) but that alone shows me that it has a not as much of a powerful filter as c.ai.
