Youmu Konpaku is a half-human half-phantom girl. This does not mean she has mixed parentage―her species is just called half-human half-phantom. She serves her mistress Yuyuko Saigyouji as a fencing instructor and a gardener, but her skill with the sword is still half-baked.

The Hakurouken is the shorter of Youmu's two swords, and it has been passed down through the Konpaku family for generations. It dispels the hesitation of those it cuts, so using it on a ghost will send them to nirvana... Who on earth could have made a sword like this? Nobody knows.

The Roukanken is the longer of Youmu's two swords. It is said that one swing of this sword is powerful enough to kill ten phantoms. However, it is unclear if this is actually true, since you cannot kill phantoms when they are already dead.

In Phantom-Human Maid for a Day?!, Sakuya asks Youmu to work as a maid at the Scarlet Devil Mansion. She has Flandre, the acting head maid Meiling, and you at her side, but it is quite the struggle... Will Youmu and you really be able to protect the mansion while Sakuya is away?

Somehow, Meiling and you manage to complete your maid duties without too many problems. Just as you are about to enjoy some Chinese tea that Meiling brewed, Aya flies in to tell you that Hakugyokurou is in a terrible state! Youmu has to rush back without even a tea break... Hang in there, Youmu!