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I don't know what surprises me the most here: That there's been this big of a controversy over a vocaloid song, the stuff that's apparently in the EULA for Kaai Yuki, or that there's an English version of Yuki.
To be fair, pretty much any song that gets popular is bound to get shat on by some people...
If by getting shat on you mean that social credit whores are losing their fucking minds because they think a "child" sang this "sexually suggestive" song, then sure.
According to the third-party source (a geocities.ws fansite), this is Laguna, though this webmaster misidentifies the characters in some of the other pictures they host. The hair looks similar so I'm going to agree that this is probably Laguna as a dragon, but I don't know for sure and wasn't able to find it on the rendezvous's original site on the Wayback (it's very incomplete).
On the plus side, the images that are both in this gallery and the artist's original site have the same MD5s, so this is probably a good source for uploads. The images are not compressed, just low res, because they originate from the very early 2000s.
This was drawn by Daoko, the singer of "ME!ME!ME!" and "Uchiage Hanabi". She posted this after an episode of Suisei's radio show aired in which she appeared and talked about how much she liked VTubers, especially Miko.