Title: Yoru no Kuni (Land of the Night) | Artist: Annabel | Show: Gangsta.
Why I picked it: This is an excellent ending to an excellent anime. Gangsta seems to be a tough-as-nails no-nonsense kind of anime on the exterior, but it definitely has depth and emotion, and this ED perfectly showcases those emotions. And the scene where Nicolas does the sign language? That jerks at me like nothing else does. Take a look at the lyrics!
And the single just came out today! The full version is just as amazing. Definitely worth a buy.