The story takes place in a time when demons are terrorizing the world. Three warriors come together and form a Blood Trinity, vowing to fight demons until the world is safe again.
One warrior, Elim, is a noble Korean swordsman. The second, Kusa, is a Japanese sorcerer. The third is a woman, Raening, a martial arts expert skilled in archery. Elim becomes engaged to Shining a beautiful girl who he has to rescue when she is captured by demons. He cannot live with her until the world is free of demons. Kusa carries a box on his back containing the bones and restless spirit of his father. He is sworn to avenge his death and find a way to let his father rest in peace. Raening has to prove that a woman and a princess can be as good a warrior as any man. The warriors travel from village to village helping those beleaguered by demons and fulfilling tasks to help the villagers. As a result of their labors they accumulate money, weapons, and powerful spells. They will need all their skill and experience as they learn the story of the Blood Sword and vow to find it and use it to kill Satan.
Akuma: Demon Spawn is a role-playing game similar in appearance to Diablo. The player indirectly controls the characters with the mouse, choosing spells or abilities through a menu or hot keys during battles - the player only needs to click on the foe and the rest of the fighting is automatic without further interaction. The player has to handle three characters instead of one, which can make quite a big difference, since there is no pause function like in Baldur’s Gate; the combat occurs fully in real time. The majority of the game is spent by exploring the maps, killing hordes of monsters, receiving better gear and improving the hero’s abilities. No longer needed equipment is sold in the villages connected to each other by teleporters.