The pain was like nothing Arthur experienced before. However despite all this, the fire itself didn't even cause a single scratch over him.
It was all thanks to the black curtain. It kept him safe and kept torturing him as well.
Arthur almost lost track of what was going on in the real world around him. The shouts of that dark angel mage while laughing and celebrating early on his victory didn't even pass through Arthur's ears.
He was in his own world at the moment. Arthur tried to control this pain using everything, however he failed.
"I… shouldn't… lose… my consciousness here!'' This was the most stressing point he had to think about and focus on.
After failing in controlling the pain all he could do now was to consider his safety after this pain would end. If he ended up losing his consciousness then he would end up being as good as dead.