Sonsaku's sister Sonken arrives at Nanyo Academy, and is almost immediately declared interim leader and thrust into battle against assassins sent by Himiko.

To save her sister Sonken's life, Sonsaku makes her way to the legendary training ground of Jofukuin. But awaiting her there are many surprises, some more familiar than others.

When Ryomou wakes up in an eerie place linked to the nether world, she fights like hell to get back to Kyoto. Meanwhile, Himiko's plans continue to progress as Chou'un makes her way into enemy territory.