Books in the My Unique Skill Makes Me Op Ev series

Ryota Sato finds himself transported to a world where everything drops from monsters in dungeons. Despite being stuck at level 1, he uses his unique S-rank drops to farm dungeon monsters and make money alongside his friends: Celeste the mage, Eve the strange bunny, and Alice the monster tamer.But everything changes when all of the item drops in Cyclo stop. Faced with a town that has no way of getting drops out of dungeons, Ryota is asked to investigate the root cause of the issue...and what he discovers is truly shocking!