You have a very talented cat!
Your cat is standing on two feet because he has discovered the joys of being taller. Your cat got tired of being picked on by all the taller cats and decided to do something about being so little. Now that he has discovered how to stand like a person he has all the best views in the place, he can scope out all the best nap areas, see all the sources of food and can look down on all the cats who picked on him. We of course encourage your cat to be the bigger cat and stop the cycle of cat on cat bullying.
Enjoy the view!