Following a tragic accident, Taro Umeboshi was whisked away into another world. An isekai.

However instead of the fame, fortune, and power of classic a RPG hero, young Taro was summoned by none other than a dungeon lord.

From here he must fulfill the whims of his new tyrannical master and help defend the dungeon from other would-be adventurers! Formations, traps, and battle strategies must be utilized due to the influx of *isekai'd adventurers and increasing challenges.