Youmu Konpaku is a half-human half-phantom who lives and works in Hakugyokurou. She's skilled enough with a blade to have been designated her mistress's fencing instructor, but she's also in charge of tending to Hakugyokurou's expansive garden―a fact that's often forgotten. The two swords (one long, one short) she wears on her waist aren't just for fighting. Youmu also displays impressive prowess with them when she's trimming the aforementioned garden. According to Yuyuko, Hakugyokurou's garden is extraordinarily vast, stretching for 200 yojanas in every direction, and even a legion of servants would struggle with the morning and evening patrols alone. And yet, Youmu does that and more every single day. Youmu's capacity for work is, in a word, superhuman.

Yuyuko Saigyouji is a ghost who has existed for over a thousand years and is the mistress of Hakugyokurou. She entrusts her servant phantoms with taking care of her, and her bodyguard, Youmu, also works as the mansion's gardener. It goes without saying that tending to the garden is a physically demanding job, but it also requires a lot of time and attention to detail. Presumably, Yuyuko appointed Youmu as gardener because of her refined swordsmanship skills, which not only allow her to cut through almost anything but also to move instantaneously.

When your schedule's jam-packed, moments where you're able to stop for a second and take a breath are a precious thing. For Youmu, those moments come whenever she takes a brief break from gardening to stroke a certain cat spirit. Youmu spends her days surrounded by the phantoms who also work at Hakugyokurou, so it may come as a surprise to learn she's scared of unknown beings, or "spooks," as she calls them. Even so, she's not able to resist the cuteness of animal spirits, and in particular, cat spirits. After all, despite how serious she may look when she's clutching her blades, she's still a lovable young girl.

It's said that phantoms, bodiless beings of temperament, don't require food to exist. However, it seems food is not altogether meaningless to them, as shown by the joy they express when receiving it as an offering. This reaction is particularly notable among animal spirits. It's unclear where she got it, but it seems Youmu brought pet food into the garden. Perhaps she did so to soothe any animal spirits she bumped into, or perhaps she aimed to offer it to the cat spirits as a way to befriend them. Until Youmu decides to share her true motives, it'll remain a mystery.

"It's you again! Have you been a good kitty?" said Youmu in an unintentionally cutesy voice. If those who knew her heard this, they surely wouldn't have believed it. Later, when Youmu returned to the mansion, Yuyuko called her over. "Hey, Youmu. Since you like this cat so much, why don't you adopt it? You'll have to look after it, of course." Youmu looked down slightly to see the cat from earlier now curled up in Yuyuko's arms. "L-Lady Yuyuko! W-Were you...?! D-Did you...?!" Youmu's ability to form sentences escaped her as her face turned as red as a ripe tomato. With a soft "Meow," the spirit cat jumped down from Yuyuko's arms and began circling around Youmu's feet. "Look, it's chosen you as its owner!" squealed Yuyuko as Youmu's heart was irrecoverably torn in two by the sheer cuteness of the little cat brushing up against her leg. In that moment, she knew she'd never be the same again.