I really like the design work you did for these bronies. It can be difficult for guys to still come across as masculine with such "girly" colors, but I think you pulled it off very well while retaining the personalities of the characters. Obviously Rarity is going to come across as feminine because that's simply part of the character: to be fabulous. Very nice job.
There's an odd vibe to them that makes me think of college students. Especially Bubble Berry/Art and Dusk Shine/Computer Science or Psychology (those are the closest things to black magic I can think of)