Berserk of Gluttony (Light Novel) Vol. 4

ROTTEN TO THE CORE
Blessed with new power after his trials in Galia, Fate returns to Seifort. He intends to wield his influence to uplift the downtrodden—those forsaken by the world for their “unnecessary” skills. But standing in his way are his cruel old employers, the powerful Vlerick family. Now, in order to save the soul of Seifort, Fate must expose the terrifying truth hidden within the Vlerick estate.

Isshiki Ichika is an up-and-coming Japanese writer best known for Berserk of Gluttony.
fame is a Japanese artist best known for the light novel illustrations in Berserk of Gluttony.