Who are the people on front cover of mortal instruments books?

* City of Bones: Clary Fray and Jace Herondale

* City of Ashes: Clary Fray and Simon Lewis

* City of Glass: Clary Fray and Sebastian Morgenstern

* City of Fallen Angels: Simon Lewis and Isabelle Lightwood

* City of Lost Souls: Clary Fray and Magnus Bane

* City of Heavenly Fire: Clary Fray and Jace Herondale