imaginary brother.
Jack is in love with Gwendolen Fairfax, the cousin of his best friend, Algernon Moncrieff. When the play opens, Algernon, who knows Jack as Ernest, has begun to suspect something, having found an inscription inside Jack’s cigarette case addressed to “Uncle Jack” from someone who refers to herself as “little Cecily.” Algernon suspects that Jack may be leading a double life, a practice he seems to regard as commonplace and indispensable to modern life. He calls a person who leads a double life a “Bunburyist,” after a nonexistent friend he pretends to have, a chronic invalid named Bunbury, to whose deathbed he is forever being summoned whenever he wants to get out of some tiresome social obligation.