If someone moves my motorcycle to take my parking spot, is that against the law?

Parking in my building is very limited, and I park my vehicle with a motorcycle in one spot. Sometimes when I leave, I park the motorcycle in such a way so that I said my spot (it's a little selfish I know). With that being said, there's this guy that actually has the nerve the move my motorcycle in the same regular position so he can park his vehicle instead! Question: would that be against the law? I live in Texas.