I very, very unfortunately know exactly the fic in question, and know that it is considered to be part of a series of other unrelated disturbing fanfics.
This is Phandom-related, as in the Dan and Phil "Phandom".
It stars Dan and Phil, two very popular youtubers (and real people!) as the main characters.

The original copy was either removed, or destroyed. Link presented to a duplicate copy rotted here: uggcf://jjj.dhbgri.pbz/fgbel/7249529/Gur-Ung-Svp/1
This piece has incredibly NSFW sexual content, gore, and a whole lot of nope. Unless you want to see your own breakfast again, I would not read.

As for the history!

The fic is currently around 4 and a half years old, and I might be wrong, but I think it was written in December of 2015? That's the earliest copy of it I could find, but it may be older. I think the author is the same of other notorious fics such as The Milk Fic and The Skin Fic (fair warning, searching these will immediately provide NSFW material.) They've garnered a lot of hatred and disgust from pretty much everyone (including the people written about, IIRC!). Honestly, I'd be down with calling this a legendary badfic. Saying the words "Hat Fic" around anyone who knows what it is is effectively using a dragon shout on them. It's bad.

Once again, this is incredibly disturbing. I'm pretty sure all of the fics mentioned above even have their own urbandictionary pages about them too, if you want to read those instead of the actual fics.

- Helsinki, scarred for life

I can't really say anything for any of the others, but looking up "The Hamster Fic" seems to lead to "The Hat Fic", which is a Real Person 'fic involving two Youtubers and some really disturbed stuff (NSFW, NSFST probably NSF4M and definitely NSFB). Thankfully I didn't have to read it as there was an Urban Dictionary article on it. Having read the Urban Dictionary article, I've promptly decided to not venture onto Quotev or Wattpad (which seem to be the only places currently hosting the 'fic).

"The Hat Fic" seems to be relatively well known, at least well enough to have at least 3 pages of Google worth of stuff about it if you type it in, although most of that seems to be from the "Phandom" which as far as I can tell are the people who like these two Youtubers stuff and possibly ship them as well. The 'fic seems to be from around 2015, or at least that's what the search results are saying.

Novastorme
P.S just after I wrote this (but before I posted) I decided to do a Search result for "The Cherry Fic" just out of curiousity (idiot me) as it came up as something related to "The Hat Fic". It's another fic involving the same two Youtubers being shipped together (at least). That's where I stopped looking as I assumed everything else would probably be along very similar lines (although I did see in the search results something saying "The Hat Fic" was definitely the worse of all of them. And also never to read it...