Erza Scarlet's Japanese Cloth outfit. I think it's safe to say we all love Erza and her many outfits (as well as a few other things) her Japanese outfit takes a more traditional Japanese samurai look and adds some Erza charm to it, to say the least.
Erza is always sexy and powerful and this outfit only enhances these qualities more than doubling her speed. She has lots of armor and outfits but this is my favorite. @VinMcCarthy