Light Novel Volume 8

Summary
With Ost's sacrifice, The party success defense against spirit turtle and Book Vassal Owner, Kyou. As Kyou escapes, Naofumi and party follows him to Other-world. As they woken to only find themselves in prison, to make the matter worst, Naofumi's level have mysteriously reset to level 1. As they entering into this crisis, they are saved by a girl who introduce herself as one of the Four Saint.