'Soul…'
An existence linking the lowly human body to the lofty realm of the universe.
'The domain of soul is a restricted area where body, soul, and universe are connected to each other, also where powers such as Aether and mana are stored…'
A limited space where only the individual themselves must have access to. A place where, despite being present in every individual, could only be entered and explored upon years of devoted training; something most people fail to achieve and even if they do so, is still almost impossible to access at a young age.
'And now even I can't enter it anymore...'
After that incident, after almost losing his life and nearly regressing, his domain of soul was also impossible to access as it was shattered beyond recognition.
