Ningen Fushin No Boukenshatachi Ga Sekai O Sukuu Youdesu Vol.1-6 Set
It sounds like you're looking for high-quality paper goods or the manga/light novel for ( Apparently, Disillusioned Adventurers Will Save the World ). Ningen Fushin no Boukensha tachi ga Sekai o Suk...
For collectors, various retailers offer official paper-based merchandise: Ningen Fushin No Boukenshatachi Ga Sekai O Sukuu Youdesu Vol