Although Han Dong has not yet fully found the answer to "what is Faceless".
However, these days of 'self-thinking', besides bringing Han Dong closer to the final answer,
also led him to find a special feeling,
the shackles of limitation on his body were unlocked, specifically coming from the constraints of humanity, which completely disappeared as he recognized his true self.
Since ascending to the S-01 world and choosing the "Faceless Skull" in prison, Han Dong no longer defines himself as any species.
Faceless and myriad faces.
If Han Dong hadn't initially 'restricted' himself to being [human], given the special traits of the Faceless Skull, he could have had thousands of identities.
Even if the Knight Squad hadn't introduced him to the Holy City at that time,
he could have survived in the area outside the city according to the traits of the skull and might have gone to the Demon towns to gain a completely different growth and development.