I'm thinking of freeloading off my parents and being a general piece of garbage
Why wouldn't you want to live independently and stop living off your parents?
I am saving a lot of money this way.
I think it is bad to want to just live off your parents instead of trying to make a living for yourself. It's encouraged that you leave your nest and start your own life after college. You should talk to your girlfriend about these issues and let her know you can't keep living off your parents.
They cannot stop me.
You should try and do things on your own for once. Living off of your parents will not teach you to do better for yourself. There are jobs you can look for online if you need more information.