Solo Leveling, Vol. 3 (light novel)

When Jinwoo gets his rank reevaluated, the results are even better than he could have
dreamed of...but more importantly, a chance to heal his mother from her strange
illness falls into his lap. In order to find the cure, he must make his way further into
the Demon’s Castle—and now that there’s finally hope at the end of the tunnel, nothing
can get in his way.