地下室ダンジョン ～貧乏兄妹は娯楽を求めて最強へ～

A dungeon suddenly appeared in the basement of the shabby house where two poor siblings, Fuyuka and Haruka, lived. Delving into the dungeon every day to hunt for the treasures and meat that monsters drop, before they knew it they have become the strongest dungeon explorers in Japan...!? (Source: Shueisha, translated)