....oookay....
That is not a normal photoshop manipulation. Do you have some sort of 3D rendering program with a 3D model of Miku? And then paste it on photoshop?
Hmmm, it's a 3D renderer (not sure how to entitle it, it's a sort of 3D motion-making software? You can let your 3D models move and dance in your PC) software called 'MikuMikuDance' (abbr. 'MMD'). It's a Japanese freeware but you simply won't believe it's free, looking at the quality of software itself and also the third-party models which are reachable on the web. What I did is that I take a picture in-game, import it into PC, do some edits (to minimalise the deviation of texture 'color' between 3D model and picture itself) and import the picture into MMD as a background picture. Then load a 3D model girl (a third-party Miku for this time), make a pose you want and do some lighting/shadow alter inside the MMD software (this can be done very precisely, from the vector of light source to lighting colors. So I said you won't believe it's a free one), finally output the product as an image file (jpg, png, bmp and many other formats; you can even specify the size you want). Since the contrast in the first picture was tad too high (shadows seem too 'black') and it exceeds the black-ness of shadow which can be rendered in MMD, so comes the difference.
The DL link for MMD itself is here (
http://www.geocities.jp/higuchuu4/index.htm), and a Wiki for MMD (in Japanese, I only understand moderately of it) (
http://www6.atwiki.jp/vpvpwiki/) to search for user-made 3D models. Many anime/manga characters apart from Miku is up for free DL. Most of the models are not re-distributable so you have to take note of that. There's some tutorial videos in English on YouTube so you can refer to them if interested.
And... a collection of my MMD-GT5 joint creation, just to show how far can MMD go with GT5... =)
Sorry for the long (and perhaps boring) texts.