In the game, you are a small shaggy blue demon finding himself in a dungeon full of fallen angels, gargoyles, wasps, etc. Walking through them loses you energy, which is your life. So you have to run and jump avoiding them, collecting gems, blood drops, energy vials, and some sort of friend-demons such as eyes and tongues. On each level you have to find the keys to open a door to a magical cauldron guarded by a beautiful elf. Levels are decorated with statues of beautiful women, old men, dragons, swords, or eye walls.
"Demon Blues" -- C64 title