Ryota Sato finds himself transported to a world where everything drops from monsters in dungeons.

While his level is capped at 1, he uses his unique skill, S-rank drops, to raise his stats—and those of his friends in the Ryota Family!

As dungeon spirits join the Family, more people ask him for help. Among them, none other than Neptune needs him for a major investigation! After accepting the request, he finds himself embroiled in a whole host of new issues. Will things go smoothly for our hero and his Family?