My F-Rank Bug is the S-Rank Hive Queen

Others awaken one bonded beast. He awakens a world-devouring ant legion. The beast egg his mother left behind shatters, and an S-Rank Hive Queen appears: devour strange beasts, evolve billions of ant soldiers. Three days of hunting, first place in the trial, S-Rank beasts turned into rations for his swarm — and this is only the beginning. Noble black magic, an underground city, a three-headed hellhound, the Lord of the Abyss... every secret awaits his blade.