Color the whole thing pink man.
Haha

Our all lusting and deviant lord/mistress Slannesh sssssuggests that you go with, dark green/bright orange, hot pink/void black and some coke red/rosey crimson for her champion, with these perfectly clashing colours he/she may even grant you the boon of having a vagina where you armpit was. For Lord/Mistress Slannesh is pleasing with his/her randomly attached organs...I mean boobs..UH! Boons! Yes his/her boons! Yessssssss.

Flourescent pink and purple. That's what I always suggest. Looks to be one bad ass fight, though :3

Whoa! Hey! Holy *#()%! You drew her! My drawing production must now explode! I'll concur with much of Lex's suggestions, pretty much like the Emperor's Children coloring, void black and crimson, with traces of obscenely bright pink.