Demonion: Maou no Chika Yousai

Based on the adult game by Astronauts: Sirius, Demonion: Maou no Chika Yousai follows the dark legacy of Astaroth, a powerful Demon Lord who once launched a devastating invasion against the human kingdom and plunged the world into war. His reign of terror was ultimately brought to an end when a united group of heroes managed to suppress him. Stripping away his formidable powers, they sealed him deep beneath the earth, burying his threat in the forgotten darkness below. Two centuries later, sudden shifts in the earth's crust give rise to unsettling rumors that the ancient seal has fractured and the Demon Lord has been revived. Driven by ambition and the promise of eternal glory, countless confident adventurers descend into Astaroth’s sprawling underground labyrinth, each determined to be the one who finally slays him. However, these eager warriors are entirely unaware that their arrival is not a surprise. The resurrected Demon Lord has already prepared a deadly trap for them, turning their quest for fame into a descent from which none may return.