Arvin was interested in Alman's weapon since the time when he tried to kill him. After all, it was not every day you see someone use chained knives as their weapon. Then on today's faithful day, his interest reached another level when he saw those knives behave as they were alive when they wrapped themselves around Alice's feet. That was quite shocking as well as interesting for Arvin.
He had never seen a heap of metal behaves like that. Except for the robots. But that thing was not a robot. Which made Arvin curious about those knives. Were they controlled by Alman by magic? Or do they have a mind of their own? They were strong enough to chip Park Go Gum's sword, so at least they were something very strong. That is why Arvin went out there and tear the arms off of Alman. He wanted to get his hand on those knives.
