Look over here: BREAKING NEWS UPDATE:
The folks over at Touhou-Online , the community in-charge of patching Touhou has just confirmed with me that the leaked name list within the game's codes that we have just reported 2 hours ago are indeed real and exist within the game file:
Or as per quoted from this French article of their community, translated into English (thanks Lunya) :
http://www.touhou-online.net/?/?/304-touhou145-demo-download=====
"In game files, next to names reimu, marisa and kasen, we sometimes find "hanako". Also, the script file which shows the scene just before "To be continue..." where we can see the shadow of the probably final boss, launchs a file called "hanako.csv". So it's probable that the final boss is a Hanako from toilets. More, it corresponds well to the story game, which is talking about urban legends.
Also, there is a file with binary data, this:
reimu........marisa........ichirin........miko........koishi........hijiri........kokoro........mamizou........nitori........futo........kasen........mokou........sinmyoumaru........hanako
(Each dot is a byte which doesn't correspond to any character)
Nothing is definitive as we aren't supposed to access those files, but it seems to be a list of characters which are actually planned for the complete version (we insist on the non-definitive term: some characters may well be removed before the game goes out for several reasons)"
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So now we have patching community sources confirm that the codes and name lists are in-fact, very real. So the chances of us seeing familiar faces from Touhou 13.5 again (Yay Holy Hijiri) is... pretty dang fine right now, I have to say; and chances are we should certainly hope to see the addition of Mokou, Shinmyoumaru... and the Toilet Girl to the community of fighting 2hu soon folks
Thanks again Touhou-Online for the quick confirmation
Sauce:
http://danbooru.donmai.us/posts/1448046-ShameimaruNamusan-
Potencial characters whose name where found in the demo's files