Charles Marlow
Marlow's name may be inspired by the Elizabethan playwright Christopher Marlowe. Conrad's father was a translator of William Shakespeare who doubtless would have known of Marlowe's work as well. Some intertextual interpretations of "Heart of Darkness" have suggested that Marlowe's "The Tragical History of Doctor Faustus" may have influenced Conrad. Charles Marlow describes a character as a "papier-mache Mephistopheles", a reference to the Faust legend. Marlow's and Kurtz's journey up the Congo River in "Heart of Darkness" also has similarities to another work by Marlowe, "Dido, Queen of Carthage", in which Aeneas is stranded on the shore of Libya and meets the African queen Dido.
Arcana Heart
is the main protagonist in the series. She is a normal high school student who shares a passion for justice with the superhero television shows she grew up watching. She also assists her mother in running the family-owned restaurant Cafe Aino, and hopes to one day make something that can be placed on Cafe Aino's menu. Her Arcana is Partinias, the Arcana of Love. An angel with two pairs of wings who can manipulate light, she is Heart's partner and friend.
, the "Crimson-Eyed Criminal", became a cold-hearted assassin after losing her family. She travels the world alone, accompanied only by a leg-less ball-jointed puppet which carries the consciousness of , her older sister. Her Arcana is Gier, the Arcana of Shadow, a creature composed of purely negative emotions that Lieselotte summons with drops of her own blood.