Kazuma's party is suddenly alerted by an outrageous letter delivered by Yunyun. The letter requested that they come to the Crimson Demon Clan's village, that is facing a threat that could mean it's ending.
One day, I-a high schooler-found a paperback in the hospital. The "Disease Coexistence Journal" was its title. It was a diary that my classmate, Sakura Yamauchi, had written in secret. ...