a camp follower

a camp follower

someone who strongly supports a person or group although they are not a member of an official organization The campaign for real ale had gathered quite a number of camp followers.
See also: camp, follower
References in periodicals archive ?
It is hard to think of General Nathanael Greene, one of Washington's most brilliant fighters who also served as quartermaster general from 1778 to 1780, as a camp follower.