There are definitely some exposure issues here; your model actually presents a rather challenging exposure situation because of the variety of colour in his fur. What I would suggest is to first evenly illuminate him using a diffuse light source and then use your camera's spot metering function to determine the exposure for the bright areas of fur. Expose the whole image that way (perhaps bracketing by 1/3 stop either way) and then use the levels/curves function of your favorite post app. to bring out the detail in the darker areas.
With respect to the question of composition, one of the cardinal rules of portraiture, whether human, or animal is to be at eye-level with the subject. The chair is a good idea, and could work well, but there is too much extra detail in the image which distracts the eye. Consider putting the chair in a larger, more open space, and using a longer focal length and larger aperture (to achieve shallower DoF) in order to isolate the subject.
Just my $00.02 worth - your milage may vary.
~John