>>716235435
(You), the Demon King, is tasked with defeating Trillion, a legendary demon with 1 trillion HP who's devouring hell, by selecting one of his loyal Demon Lords at a time to train and fight. It's basically a management sim with a single basic dungeon for stat-ups and fights against Trillion every X days where your girl slowly whittles at its HP. The game's main draw is that your girls can die permanently, sacrificing themselves to weaken Trillion severely each time, and the game takes itself extremely seriously despite the Disgaea-esque vibes so you actually get to feel the weight of your failure.