Mamonogurai no Boukensha: Ore Dake Mamono wo Kuratte Tsuyoku Naru

Rudd is an E-Rank adventurer with a talent for status immunity that is considered nearly useless. In a city where success in labyrinth exploration defines one's worth, he is an outcast who survives by doing low-paying jobs and dealing with guild conflicts and dishonest adventurers. After being abandoned and left to die with no resources, he resorts to eating the flesh of defeated monsters.