If you're just using Touhous without Gensokyo, put the story in /others/.
Otherwise you can put it wherever else it would fit. People have been putting stories in /others/ that would have been fine in /th/ or elsewhere since forever.
Doesn't really matter. We've had OC's from outside and inside the border get put into /th/ and /others/ - it's mostly just about story location (or not giving a fuck and posting wherever).
>>9722 Yeah, what >>9725 said. OCs are pretty much everywhere, in many stories on all boards. Granted, in a lot of cases they're just the protagonists, but still.
Maybe /th/ and /others/ were popular because they won't get 'restricted' on the characters or pairings.
For an example, when reading a story in /shrine/, you'll expect it have Reimu/Suika. Now imagine if Treia's dead story in /th/ moved to there, since it's supposed to focused on human village. Reimu was only makes an appearance in three updates, Suika even less, and that other shrine maiden get much more screentime that both of Reimu and Suika combined, not to mention that she is the more potential love interest, since anon rooted to her. Isn't it kind of weird to have a story in /shrine/ but the protagonist ended up with Sanae?
Yes, I hate him for being lazy ass and leave my favorite story on page 2.