Just as a warning if you have the physical book don't look at the back cover or you might recognize a familiar face from the past that shows up unexpectedly (to those that meet them) leading to a most certainly deadly turn as Subaru does what he can to help the people in the sanctuary return home. In the meantime Emilia must continue to face her own past to pass the trial of the sanctuary regardless of how dark it may have been (somehow I doubt her trauma is covered in the Frozen Bond sub series.)