The protagonist of Heaven Cent is Prince Dolph, shapeshifting son of King Dor and Queen Irene and younger brother of Princess Ivy.

The story begins with Dolph, a pre-teen, setting out on a Quest with his designated Adult Companion Marrow Bones to locate the magician Humfrey, who had been missing since Vale of the Vole.

The story begins with Prince Dolph lying in his sister, Ivy's, bed watching her magical tapestry which shows images from the past and present of Xanth.

Queen Irene decides that Dolph is at a fine age to set out for a quest, but as long as he takes with him an adult companion.

Marrow is a walking, talking skeleton who has the ability to transform his skeletal body into many shapes as long as Dolph gives him a good kick in the tail bone first.

Once Dolph and Marrow set out on their journey they realize their first stop must be at the Good Magician Humfrey's castle to investigate for any clues to his disappearance.

Each rose color stands for a different emotion: white for indifference, yellow for friendship, pink for romance, red for love, and black for death.