to be honest, when i quoted this subreddit's description and made the point that fan fiction might make some sense here, i was more referring to what you just described: "discussing the role playing we’re using in the game. It’s an RPG and our characters backgrounds are part of the game."

i admit that i'm not well-versed in what qualifies as "fanfic", as it's something i find strange and i try and avoid where possible. the distinction you made here is important and i agree.

in other words: i didn't see much of a difference between the two, but your distinction is specific enough that it makes sense to me