A lone woman appears when Kathleen is in danger. Is she an ally or an enemy?! Will they be able to escape from the desperate situation within the tunnel? Sensui's past is finally revealed, along with his history with his Master and the origin of his dual wielding style.

When the group makes a pit stop to try and allow a wounded Sensui to rest, Yurika is stabbed by Gibier. Yet even as Yurika's injury brings great sadness to them all, a swarm of Gibier attacks without mercy... Can they make it through this disaster?!