On top of it all Rainbow Six: Siege as it stands now is more broken than it was at launch because of the latest patch thats fucked up headshot hit detections,
I believe it's a custom artwork for the CD being sold in Japan. That art on the Steam store page is actually cut off at the top and bottom since screenshot gallery had to be cropped to fit the 16:9 aspect ratio. The full image is square and contains other characters from the game. A high res version is also included with the soundtrack download.