Hello, I'm just doing some blatent self-promotion. Check out my fanfiction.net account here if you're interested: [ http://www.fanfiction.net/~duweedavisii]
I've written three fanfics for Touhou, perhaps you'll be interested if I showed you the OCs I've... quite haphazardly thrown in!
This is Mateyuu Dawitsu, the part-time antagonist in Touhou Doujin: Dawitsu's folly, and the sort of protagonist of Touhou Doujin: Holiday edition. I called it that because originally I hand-drew a comic, but now it's sort of been overtaken by the fanfic version. Eh, I suck.
He's a Youkai of some kind, but he never cares to elaborate. However, seen as he was born and raised in the outside world, he's lived alongside humans long enough to not want to eat them. He does eat meat, but he has a strict non-humanoid policy. His signature ability is the ability to copy any attack he's observed or gained detail on. After reading Aya's notebook, he became capable of just about any Danmaku there is, but has no dangerous abilities beyond Danmaku. He, his Shikigami, Yutaka, and his mansion were all spirited away to Gensokyo.
In Touhou Doujin: Dawitsu's folly he steals Flandre's Laevateinn for a similar reason to Tenshi's antics- boredom, and an urge to introduce himself to Gensokyo. He seems to be an otaku, and upon meeting Reimu and Marisa (who had come to resolve the incident) he doesn't seem to be bothered that he's about to be foiled, but rather is glad to see what he claims are the main protagonists of Gensokyo. He later battles Yukari Yakumo, who wishes to take his Shikigami for her own. His unoriginality was what crippled him, and he ultimately lost.
However, after befriending Patchouli Knowledge and Sakuya, and taking in Ran Yakumo and Chen, they managed to work out a ransom that ended up meaning Dawitsu won both sides, getting Yutaka back and keeping Ran and Chen.
In Touhou Doujin: Holiday Edition, he decides to take Patchouli and Sakuya to see the the outside world at Christmas time, by taking advantage of Yukari Yakumo being knocked out (by Chen with a frying pan). Leaving while the Border was weak, they left Gensokyo temporarily, and got accompanied by Aya Shameimaru and Suika along the way.
He doesn't seem that bad a person, however, he's highly arrogant and at times inconsiderate. There is one thing that makes him stand out though- his kindness to his Shikigami. He loves Yutaka with all his heart, and after taking Ran in, he shows her affection also, tries (in vain) to get her to stop calling him master. He has a notable amount of self-confidence, and eccentricity to go with it, his mansion being filled with Surrealist art, Anime, and several intricate (and at times, dangerous) homages to Video Games the rest of Gensokyo haven't even heard of. His self-confidence is often his weakness, turning into overconfidence easily... he's under the impression he's the most powerful in Gensokyo, but in actuality, he's just a shadow of the most powerful.
On another note, when he creates familiars, they resemble Chibi versions of himself.
Yutaka Hadekawa is a Youkai Magician, who similarly to her master, Mateyuu Dawitsu, has spent most of her life in the outside world, living with humans. She too has formed a close bond with humans, not wanting to harm them in any way.
She's far more pacifistic than her Boss, and is also far more intelligent, but yet prefers the role of Shikigami to being in charge. She first met Dawitsu in a market stall in England, and was a Japanese immigrant who had lost everything.
Dawitsu took pity on her, and took her in to his mansion. He began to fall in love with her, and made her head servant in the mansion almost immediately. He took her out to dinner and was about to confess his love, but in the end just admitted to being a Youkai, which Yutaka in turn admitted. So he stopped his conquest, made an agreement with her that should they come into trouble, she'd back him up. Eventually the other servants caught on to Dawitsu's favouritism regarding Yutaka and quit. Yutaka regularly used Dawitsu's library, and went from a non-training Youkai Magician to a powerful one indeed.
She decided to specialize in supportive magic due to not liking it when she hurts people, and became adept at controlling the environment, which in turn helps her Boss out in battle as he performs certain spellcards better in certain places. She sort of describes it as 'programming the surroundings', saying that you merely have to simultaneously control all the variables of the area you're changing.
Dawitsu has attempted to copy this ability, but failed due to his inability to multitask as well as a woman.
Yutaka is highly friendly to anyone who treats her well, but will be overly complex and confusing to anyone who treats her with hostility. She likes Patchouli Knowledge a lot, and often trades books with her. Yutaka admitted that she is actually into other girls to Dawitsu (crushing any hopes he had of being with her in that sense) and ever since, Dawitsu has been passive-aggressively trying to get Yutaka to just ask Patchouli out.
She is a simple-minded, yet intelligent girl who is utterly devoted to her boss, and even under the custody of Yukari Yakumo she wished for nothing more than to be back with her boss.