Sounds like a typical Tortie, amplified by being a Maine Coon. We have a Mother/Daughter pair of DMS Torties, daughter turning 4 next March and Mom perhaps a year older. The Daughter, Mischa, joins me here in the desk chair by sliding down behind me from the arm. She then proceeds to attempt to push me out of said chair. Sometimes it works, as she has realized if she applies her paws to my back and slightly extends her claws.....I leave.