...
the manha name is just wrong... it should be something like "The Cursed Skeleton" or "The Skeleton of Missfortune".
Usually every mc is a prague that brings destruction and chaos wherever they go... but this one only brings death to his summoner/owner.
edit:
btw, I wonder how strong he would become if instead of passively waiting and appreciating the beauty of his killer killing spree, instead he himself kills the necromancer... even if he doesnt go to lv 100, it should give nice bonus... he never can save them anyway,,, at least that would be somewhat useful
edit2:
@Prinnyfoof
I'm just joking, I have no idea what the name is... just that so far the mc hasnt bothered to protect any dugeons (the actual title do suggest it), but he does brings misfortune wherever he goes, so I came up with one... the truth is, this is based on a novel translated as "The Gate of Good Fortune", but as mc is aways miserable, me and others readers refere to it as "The Gate of Misfortune".
Same thing seems to happen with this manwa. I very much suspect that author messed up and has no idea where to go with the story anymore.