Subjects with strong lines and interesting shapes may be best photographed using back-lighting, or at least a significant element of illumination from the rear. The camera must of course be shielded from the light source used for the back-lighting, otherwise there will be problems with flare. The normal approach is to place the back-light slightly below or above the subject and direct it towards the rear of the subject. Alternatively, the back-light can be directed at a reflector oar a white background to provide diffused back-light.
If the objective is to produce highlights around the periphery of the subject, a dark background is obviously preferable.