Anon finds himself in the middle of a weekly battle between the Main six and *gasp* the twin sisters...in CANTERLOT!? Ya, I know, not a big twist but still. He has no memories of why he is in Equestria, because of course he doesn't know, and it all moves on from there.

Image artist fire-sprite can be found here: https://www.fimfiction.net/user/fire-sprite .