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?