ahaha I think you're asking the wrong guy but uh scratches head

okay, so some of the hottest bottom Kyle I've ever read is hidden on the kink meme. afaik Anon hasn't uploaded this anywhere else:
https://south-park-kink-meme.dreamwidth.org/445.html?thread=78525#cmt78525 (mob/Kyle)

when I say this reads like it was written in one feverish sitting, I mean it in the best way because the frantic energy of the writing matches the tone of this piece so perfectly it should be studied.

Tentacles? Tentacles by Rainbow_Convection
https://archiveofourown.org/works/50706469 (Kenny (Mysterion)/Kyle)

Rainbow fics are always a banger and this one has tentacles if you can believe it!! just great monsterfucking plain and simple

might last a day (minus forever) by cherryvanilla
https://archiveofourown.org/works/420889 (Cartman/Kyle with past Stan/Kyle)

this is an older fic (in the grand scheme of things) and technically they switch in it BUT it's definitely that vintage mountain kyman/bratty Kyle that I find people look for when they want bottom Kyle forward fics. there's scenes from this I've never been able to get out of my head and the smut is top shelf imo.

here's a kyman rec list I made a while ago that has a mix of top and bottom Kyle although it's top heavy because I worship at the temple of bottom Cartman. see, it's not about Kyle for me.
https://retrospring.net/@shortkingkenny/a/111293811561394631

and you should check out my friend Sam kyman4lyfe because she writes a lot of bottom Kyle and in fact just posted something where Kyle gets a bunch of holes filled by a bunch of guys:
https://archiveofourown.org/users/kyman4lyfe

and here's her curiouscat because she can help you with this question so much better than I can:
https://curiouscat.live/kyman4lyfe

sorry I couldn't be more helpful! I'll post these links on twitter too.