Now I'm a Demon Lord! Happily Ever After with Monster Girls in My Dungeon (LN) (Associated Names)

One day, I woke up only find out that I’d become a Demon Lord, an individual responsible for protecting a dungeon. The world I’d been spirited away to was one filled with violence. Gigantic monsters wandered through it and competed with each other each and every day for the right to survive. I had no…