The only thing I know about FeFe is that, for whatever reason, there was a period where YouTube would recommend me shorts from her, that I had no idea were of a vtuber under I watched them. They'd be a short clip from an anime - usually presented with anime butt in the thumbnail - that'd play out, and then freeze at the end, where then FeFe'd appear, with her terrible facial piercings, to make some dumb comment.
That was it. That was the whole short. And she kept making these, and they kept appearing in my recommendations.
The pointlessness of these shorts, and her dumb face, however, is not why I hold ill will toward her. I dislike her because, neither in the description nor the comments, did she supply a source for the anime. It always came down to some respectable citizen in the comment section to do the Lord's work and provide the source.
For this, she has my ire.