dont know what your price rang is but i would recommend a 35mm with a wide aperture. maybe one like the Nikon AF-S NIKKOR 35mm f/1.4G. that one is a bit expensive though. they also sell a 35mm f/2.8 and 35mm f/1.8 if not 35mm, 85 mm or 50mm are also good. it is dependent on what you will be using it for.