Here is Whistler, the fateful companion of former CorSec agent and current Rogue Squadron member, Corran Horn. Whistler has been with Corran since his beginnings in the Corellian Security Force, assisting him in solving some of Corellia's hottest crimes and saving Horn's neck from time to time. After Corran left CorSec Whistler joined him in his new role in life, a fighter pilot for the New Republic's famed Rogue Squadron. Whistler was first mentioned in the novel X-Wing: Rogue Squadron and is detailed in the colors of CorSec.
Whistler is a simple repaint of a Wave 1 POTF2 R2-D2, flat black on the body with standard green in the grooves. When I made Whistler 2 years ago I did not have a visual description of the little astromech, so I painted him in CorSec's colors. It wasn't till Michael Stackpole's I, Jedi came out this past year that I saw that I got Whistler's main body color all wrong. It should be white, not black, go figure. I left the paint job as is, I just like the darker visage it gives.