Rorgis' mother, the 【Eiyuu】 Ruskatia, was known as the 【Defender of War Souls】. It's said that she used a battle axe to reclaim around half of the current Sternbild Kingdom's territory during a dark age when monsters that were more powerful than today's monsters were prevalent.
Satori intruded in the war that occurred between Ruskatia and another tribe.
The war ended after three days and nights when Ruskatia beheaded their leader. The damage done by Satori to Ruskatia's companions that participated in the war was enormous, though the damage the other tribe they were fighting suffered almost completely destroyed them.
Ruskatia became pregnant due to a spurt of the Satori's blood. Though it's not certain why she gave birth to Rorgis, her sworn enemy's child, but the circumstances caused the two to become one.
However, Ruskatia had lost the ability to fight on her own, so instead she trained Rorgis so that he could fight on his own. This is the story that was carved into a lithograph that's passed down among the royal family.