• The hero. jk rowling-harry potter * shakespeare-king arthur
• The girlfriend. hermoine granger [she's not his girlfriend, but they were close] * guinevere
• The third party. ron weasley * lancelot
• the magician. dumbledore * merlin
• the significant father. james potter * uther pendragon
• the person that gives the hero the weapon. lily potter * the lady of the lake
• the extra who died. cedric diggory * elaine of astolat [the lily maid]
• the bad guy who's somehow related to the hero. voldemort * mordred [half-brothers]
• a witch who flies and is able to change shape [also has nothing to do with the story. professor mcgonagal * morgan le fay
• the organisation. order of the phoenix * order of the bear
• the fighters. the wizards of the ootp * the knights

Since shakespeare died first, and she's still living, its obvious she copied him and not the other way round.

King arthur is gay. XD