The origins of the lyrics in each part.

Prologue

Cannonball by Damien Rice (O)

Parts One to Five

Wicked Game by Chris Isaak (Heart-Shaped World)
Black Eyed Boy by Texas (White On Blonde)
Viva la Vida by Coldplay (Viva la Vida)
Otherside by the Red Hot Chilli Peppers (Californication)
Waking Up Beside You by Stabbing Westward (Darkest Days)