This is Mo. He is a male Guinea pig and he is ridiculously floofy. Guinea pigs are great starter pets, because they are bigger then hamsters, so harder to lose. They are also calmer (and fluffier). The most common breeds are Smooth-coated, Abyssinian (I think Mo is Abyssinian), and Peruvian.
Go to this link to learn more about Mo: https: //www.aear.org/pets/view/2085/guinea-pig/mo#.VQtJ1xDF_YM