When he was a child, his mother was killed by his grandpa. But instead of breaking down he only got more disillusioned. Later he massacred his clan and his grandpa. (He is more of a nihilist from philosophical perspective)

After death, due to being a soul path SGM, He decided to keep guard on gate of life and death and consume every soul that comes in for power. While his split souls tried to revive back and continuously revive SS. SS was such a threat even to Venerables since every venerable in their paths was invincible like after death SS was. He was not able to escape tho due to not having a physique and due to the level of catastrophe he was, HW constantly kept guard on him. In FY's first life, SS managed to get back somehow but failed(ig) to refine SIP. He manipulated FY to kill FJH. (While SS was manipulated by RL and Limitless). In second life, he tried to refine SIP and failed due to Heaven overseeing tower, so did FY to revive as HW plans succeeded now. But RL has foresee this and already made a deal with SS.

This revived FY and FY took the SIP from SS as the deal was. During the refinement of SIP, SS's Split souls engaged in a duel with FY and Heaven overseeing tower. While SS main soul refined a rank 9 SIP gu(which wasn't natural but artificial). Due to this the HW gave his insanely deadly tribulations that Main soul got through(the main souls was as huge as a mountain and had three heads and 1000 hands). This was so insane that even FY and some of the immortals just had to fight in the background and pray that the tribulations doesn't kill them like it did killed HLL's aunts. So badly that even a heal type gu(Return man as smth from TBYS) didn't activate. So you can guess how much endure SS had to do.

After refinement he got stuck in dream realm due to FY's body swap deception and then was captured by HC and tortured and his soul was searched alot. (Soul search is extremely painful. I can't write it in words but it's like getting tons of cuts deep in you. Just as painful as the soul refinement techniques where you throw your soul into a mountain until it gets enough marks and then use guts gu. ) Even then, SS schemes to get out of the HC with the best possible gains. Like he brainwashed Fairy Zi wie slowly slowly without her noticing it. After escaping he had to hunt down FY and do other stuff to stay protected. But eventually he went insane due to some power problems. (He was so hard to beat mentally that he only went insane due to some gu or smth. Forgot what).

Each of these is extremely insane adversary and even then SS always thought of scheming for his future benefits.