It would be interesting that he uses that look in order to get close to his chosen prey as well. A kind of camouflage that he would definitely enjoy. And his appearance can change depending on his shape-changing.

Wow he's such a dramatic jerk. I love him so much. All the flowing robes that look like feathers and claw boots.

I mean, Reaper is mostly immune to bullets anyway. He just turns to smoke. It's the electricity he needs to watch out for.