>>/37554/
Found it! It was a "diary of a 13 year old girl" hosted on a literal GeoCities site. The writing style is nearly identical to Miles' one, and this 13 year old girl even has sex with a nude artist named Eliot (his real name?). 
https://web.archive.org/web/20091027072015/http://geocities.com/melisasmithus/
 >>/37556/
Cluesforums is also like POM in the same way, but trying to make everyone believing what it says look insane by association. But yes, there's some incredibly sinister stuff going on between Josh and Miles, especially isnce Josh owns the only forum he posts on.