The comments below are a little picky so don't take them to heart...
I'm guessing the 2 are brother and sister but his hand position looks fairly awkward. If they are a couple, then his arms around her from behind may have looked my more natural.
The focus looks slightly off, perhaps on his shoulder so both faces look very slightly softer than they should be.
Lighting on her right side is a tad too intense but overall the strobe positioning looks good to me, although I agree a reflector left side to reduce the shadows may have been better.
The composition looks about right, and her smile is great... By and by, apart from some minor issues I've mentioned above, it's a very pleasing image, and it's almost there...