
Dont expect too much.. If I'm not mistaken, this manga is adapted to this novel:
http://www.novelupdates.com/series/slave-harem-in-the-labyrinth-of-the-other-world/
which basically has "perveted protagonist", "breast fetish", "sex slaves", "loli", "polygamy" and ect. as tags.. ╮( ̄▽ ̄)╭

You ever read Arifureta? ( http://www.mangago.zone/read-manga/arifureta_shokugyou_de_sekai_saikyou) Its good. Also, Re:Monster ( http://www.mangago.zone/read-manga/remonster/) A bit of harem but you really forget it's there, there is so little. Really more of an action. Third, Tondemo, its less action and more fun times cooking. ( http://www.mangago.zone/read-manga/tondemo_skill_de_isekai_hourou_meshi/)

Already reading RE:Monster. And the harem is definitely there and noticeable. It's not focused on much, but he gets to bang half a dozen women after pretty much every fight. And most of his main entourage is women.
Arifureta is indeed in the ballpark of what I meant though yea. Read some of it, but updates feel kinda slow sadly.
Tondemo has no harem yet indeed, though it only just started so hard to tell how it will be in the future.

This entire novel boils down to - go to dungeon, make money, buy slaves, have sex, back to dungeon, make more money, have sex, buy more slaves or lusting after other women, then go back to the dungeon, make some more money, have sex, buy more slaves, repeat ad infinitum. I gave up on it after some chapters.
I really hope this manga keeps up with the gory parts, and doesn't turn into another generic 'other world' story. Also, please no harem this time...most of the other world manga seem to include harem for some reason. >_<