It may be he's licking it or about to skewer with with his dick or just ogling it or showing it to the camera.
http://www.thelusted.com/galleries/karupspc/hardcore/8ryp1k2/karupx.html
http://www.thelusted.com/galleries/karupspc/hardcore/8ryp1k2/karupx07.html
The contex (the girl and gallery)...
