Youmu Konpaku is the fencing instructor and gardener of Hakugyokurou. She is also a servant to Yuyuko. Although Youmu may be half-baked, she is loved by all for her hard-working attitude... However, it seems that the Youmu you met in a parallel world is a little bit different.

"Lady Yuyuko, please let me carry the large plate." "Don't worry, Youmu, I can handle this." "Aaah, watch out!" "Whoops!" A little bit different...? No, maybe she's practically identical. At least in an everyday setting.

Doooong... Doooong... An ominous sound like the tolling of a bell echoes throughout Hakugyokurou. The Hour has been struck. The sound seems to be coming from the direction of the Saigyou Ayakashi, the large ancient cherry blossom tree. All who hear it must go to fight.

The Hakugyoku Arena is the name of the massive stage used for fighting in this parallel world's Hakugyokurou. The duels fought here are called matches. It has been revealed that Yuyuko, Youmu, Ran, and Chen are in charge of managing them... But who established the rules in the first place?

"...All right." Amidst the ringing, the Youmu dressed in black adopts a severe demeanor. She must go to the arena. That is the rule, her duty, her promise, her prayer... and her curse.