The life of Youmu Konpaku is a very shadowed one. There is no memory of her parents, or much of her past life. She has been training with her sensei, Youki Konpaku, for as long as she can remember. That is, until he disappeared, and she had to try and teach herself the rest of her incomplete style of swordsmanship. She has since been serving as Yuyuko's servant and her 'guardian' of sorts. Though she has a straightforward and focused personality, it conflicts with her mistress' own...
Youmu, as mentioned in her background, is a very straightforward and focused individual, who keeps onto her tasks and does everything she can to get her objective done. With more serious tasks, at least. On more simple tasks, such as small trips to the Human Village, her rather soft and almost shy personality starts to show. She's not one to pick fights, or even start them, unless she's threatened or insulted. If someone apologies before she reaches for her swords, she might consider letting them off the hook.
Youmu's ghost half comes not in the form of her being half spectral, but instead, an actual ghost half that flows around her form at all times. Though she never refers to her ghost half by name, people sometimes just call it 'Myon'.