a supporter (of an opinion, a political party)

supporter or follower

a kind of small sea-animal that fastens itself to rocks, the bottoms of ships etc

parasite

supporter; admirer

person who believes or has great interest

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

follower

a worker who, in order to win favour, obeys orders too readily

sycophant

an animal or plant living on or in another and getting its food from it; a person supported by another and giving nothing in return

something that exists by taking from or depending on another

a simple sea-animal with a body full of holes and able to absorb water easily; one of these or something similar, used for washing, cleaning etc; sponge-cake

moocher

a person who accepts an offer from a person selling something

something that exists by taking from or depending on another