>>84974
For what it's worth, it was posted on the "previous" Gurochan to the "Pussy Pain" thread in 2019, by an anonymous poster, with the text "this is just a test":

https://archive.guro.wtf/g/res/9841.html#q68434

... but I don't know if he's the original artist and the "test" is about testing how the animation looks, or he's simply a reuploader and the "test" is about testing the uploading of .gif files or whatever.