A kid named Light is the only human member of the adventuring party known as the Concord of the Tribes...but humans are by far the weakest of the races. When his comrades abandon him to the lowest levels of the dungeon, Light resorts to the gift of Infinite Gacha to create a harem of Lvl 9999 allies! With his new, and sexy, friends, Light can escape the dungeon, and more importantly, take revenge upon the Concord of the Tribes, and perhaps even break the entire world!

Full title: Backstabbed in a Backwater Dungeon: My Trusted Companions Tried to Kill Me, But Thanks to the Gift of an Unlimited Gacha I Got LVL 9999 Friends and Am Out For Revenge on my Former Party Members and the World (Manga)