All of the monsters you slay in Soul Sacrifice were once human. The Harpy was a woman of noble birth who fell in love with a fruit vendor. Everyday she stopped by and bought a bunch of fruit hoping to attract his attention. As her love deepened so did her appetite and she grew in girth.
One day, without warning the merchant moved to another town. The heartbroken woman heard the whispers of darkness and transformed. Her extra baggage became clay. Wings sprouted from her back and she flew to the next town. Rather than being overwhelmed with jealousy, her appetite took over and she swallowed the man whole. Now, the Harpy flies in the sky looking to swoop down on her next meal.
Cerberus was once a man who longed to protect his hometown from savages. With a sword in hand and two dogs by his side, he held his mission in his heart. What the man couldn’t defend his home from was a disease that spread throughout the town. Corpses piled on the street and despair set in as the man sealed the gates. Barbarians raided the town one night and stabbed the man in the back with a spear.
While knocking on death’s door, the man heard a voice asking if he would sacrifice for the "most important thing" to him, which was defending the town. He followed the voice and with a sorrowful shout the man was fused with his pet dogs.
It is said this town still exists in the world, but once you enter you can never leave.
Soul Sacrifice is slated for release in Japan this winter.