Someone who likes to be nude, but not around other people. He/She often takes off their clothes when they are alone at their house and not expecting anyone.
When his parents aren't home, Jim takes off his clothes being a secret nudist.
Someone who likes to walk aroud without his/her clothes on when they are alone, usually in their house.
When her parents werent home, Jim would take off his clothes and walk around being a secret nudist.