Mukashi Tasuketa Saijaku Slime ga Saikyou Slime ni Natte Ore ni Natsuku Ken

Synopsis

“I never want to lose someone important again…” Bullied and ostracized, I was just a loner—until a reckless dare sent me into an SS-rank dungeon. Hopeless. Helpless. Facing a Black Dragon far beyond my power, my end seemed inevitable… Then it appeared. A little slime I had once saved— Now evolved into something terrifyingly powerful. This is the story of how the weakest boy and the once-weakest slime form a bond that will change their fates— A tale of growth, loyalty, and the unstoppable rise of an unlikely duo.