Karen has light brown fur with white markings on her face and ears, the latter of which have black tips. Her eyes are blue and she has medium-length horns. Her outfit consists of a white buttoned, collared shirt covered by a blue suit that matches her eyes, as well as black glasses.
When Buster Moon and his troupe arrive at the Crystal Entertainment building in Redshore City hoping to audition for Jimmy Crystal, Karen, the receptionist, refuses to let them see him because they have not scheduled an appointment with him. She forces them to leave, but later fails to recognize them as they sneak past her while disguised as janitors.
"Sir, do I need to call security?"
— Karen, threatening Buster
— Karen addressing "Ricky", who is actually Meena in disguise as the employee, trying to sneak herself and her friends in from behind a Zamboni