Why should Luca care?
This world never accepted him in the first place! He was simply outcast by society and all realms whether it be a demon, human or heavenly realm!
And so he decided to forge his own fate.
So he changed.
From Human to Spirit.
From Spirit to Demon.
He had many forms along the way, many names along the way, many relationships along the way.
But no matter what he tried to sever it all.
Thread by thread he sliced apart all connections so all that remained was nothing.
And so they had nothing but fear.
Fear of the fate that 'it' wanted to create.