The so called 『Enjoy the Human Lives Show Humans Sent to Another World With a Cheat』was trending amongst the Gods. Kanbara Kanata, one of the chosen humans ended up incurring the Evil God's wrath and as a result, was sent to the worst dungeon,《Cocytus》. But, in a place where he was supposed to lose his life, he met Lunaire, a self-proclaimed misanthropy immortal girl. He was saved by her, who then decided to train him 'till he could at least protect himself.

「Master, I think… I've become strong enough.」

「It's Not enough! Erm, outside of this dungeon is a dangerous place you know!」

「Seriously!? More dangerous than this place…」

This is the story of Kanata who was trained by his master, who easily succumbed to loneliness, till he became the greatest hero of legend, and yet was unaware of it.