Solo Leveling, Vol. 1 (light novel)

The weakest of the weak, E-class hunter Jinwoo Sung has no money, no
talent, and no prospects to speak of. And when he enters a hidden dungeon that
fateful day, he ends up being left to die in the aftermath of a horrendous
tragedy. At death's door, Jinwoo is suddenly invited to be a "player" by a
mysterious voice. Desperate to live, Jinwoo jumps at the chance...but what is
this strange new leveling system that only he can see?