He was a young man with a black and white color scheme. He wore a black and white, long-sleeved shirt and a black beanie with white stripes.
On a mission against KNIFE, the heroes consisting of Dune, Claude, and a third member have lost against Baekmorae. Dune was conflicted when Baekmorae left the scene with Sewol and a bomb set for the heroes. Although the third member was heavily wounded, he coughed, which meant that he was alive. On the other hand, Dune wasn't sure if Claude was still alive and believed that if he received help, Claude's health would improve. Wounded as well, Dune knew he didn't have the strength to escape with both Claude and the third member, therefore he made a mistake he would forever regret by choosing Claude.
After making it to safety, Dune met with his superior who made a call that there was one survivor. Confused, Dune interrupted that there was Claude as well. His superior corrected him that it was one survivor, confirming that Claude had been dead from the start.