a person or business that represents, or that manages or arranges the affairs of, another or others

person representing an organization or person in business

a person who helps another (especially as a deputy or as a junior worker)

helper

a person who helps

assistant

a faithful supporter, especially one who obeys without question the orders of a leader

follower

an army officer below a captain; junior officer in the Navy

assistant

a person who protects; something made or designed to give protection

guardian