Youmu Konpaku (EntityTopic, 8)
From Compile Worlds
Youmu Konpaku is a half-ghost half-human (Don't ask) that serves the ghost princess Yuyuko Saigyouji with great dedication. She's very focused, but also somewhat immature and scared of scary stuff, which makes her a likely candidate for teasing, 'specially from Yuyuko-sama's. She still does her best, though.
Like Ran Yakumo, Youmu's mistress' friend's shikigami, she's extremely loyal and powerful. Unlike said kitsune, though, her boss is more a ditz than a lazy bum and is sorta concerned for her.
She's half-baked, yes. But she can wield two swords, too. One is the Roukanken, the sword forged by youkai, and the things it can't cut are next to none! ... sorta.
Oh, right. Not only does she appear as a playable character in Imperishable Night with Sakuya Izayoi, but she also appears in Ten Desires alongside Sanae Kotiya.