Ura Dungeon Oku-san

Story

After the Demon King was slain, a "hidden dungeon" suddenly appeared in a frontier town, said to be overrun by unimaginable monsters and to hold unbelievable treasures!! The newlywed Yui, about to attempt the dungeon, carries a certain secret...!? The level-99 martial artist who saved the world changes jobs to a level-1 housewife, only to be dragged into tackling a brutal dungeon!

Inhaltsangabe via AniList (Englisch).