The timing on this makes me uncomfortable. First during her holiday, and now when she's at a convention. Whoever's doing this is intentionally picking the worst times for her, either to prevent her from handling the situation, or to try to ruin her mood during her holiday. It has the hallmarks of a deliberate attack on her.
I don't know if it's real or fake, although a shop is possible. Say, someone finds a Keeki look-alike but notices it doesn't have the telltale moles. Adding them only requires darkening spots, which wouldn't necessarily trigger Photoshop-detection that relies on things like the JPEG grid not lining up due to pieces of the picture moved around.
I'm confident this isn't any content she released for sale, even to high-tier patrons. Patreon's terms of service wouldn't allow this type of content. Actually, her spicier gravure sets (Strawberry) were only sold on Etsy, not Patreon, probably for this reason. She was heavily reliant on Patreon for her income at this time, and it's doubtful that she would have risked it by blatantly violating TOS. Even at top tier, it was a common trick for people to increase their sub, download all content and drop their sub before the payment came in, and Keeki was aware of this. Even distributing porn off-site in exchange for Patreon subs is strictly against their TOS. I'm highly skeptical of the theory that this came from Patreon. There's just no way.
She also never had an Onlyfans, despite what people occasionally suggest. She did tweet once saying she was opening an Onlyfans, as I recall, but it was an April 1st joke which led to a Rickroll. Keeki still held onto her dream of being an idol in Japan (a performer required to have a squeaky clean reputation - idols get fired just for having boyfriends) right up until she blew a once-in-a-lifetime working holiday visa to spend a year in Japan just as COVID hit in 2020. Publishing porn, or even publishing on a site best known for porn, would have been unthinkable. Lewd cosplays were the limit in terms of content she was comfortable producing.
In other words, I can only see four plausible scenarios for this, none of them good. One, someone is distributing fakes for the specific purpose of harassing her or damaging her reputation. Two, it's revenge porn from a former lover. Three, it was privately distributed to someone other than a lover, never publicly published, and explicitly distributed without her consent, which is fundamentally the same thing and still falls foul of laws prohibiting distribution of non-consensual intimate images. Four, it was taken for personal use and never authorized to be distributed to anyone, but someone acquired it by hacking or other means. Every one of these scenarios is illegal.