Koware Skill De Hajimeru Gendai Dungeon Kouryaku
Summary
It's been several years since "dungeons" appeared all over the world. Ryosuke Mizuki, a company slave, is present at the scene where his workplace was swallowed by the dungeon and gets the cheat skill “Skill Book”. Taking this opportunity, will he change his dull company slave life and challenge an unknown adventure...!?