Suzy is a Piper's Child (children brought to the House by the Piper) and, until the story has begun, an Ink-Filler, Sixth Class. She was later promoted by Arthur to a higher position: Monday's Tierce, assistant to Monday's Noon who had previously been Monday's Dusk. She is a Reservist for the Glorious Army of the Architect, and in Superior Saturday has given herself the title of General. She is one of Arthur's most loyal helpers, and friend, constantly assisting him whenever she can. She often disobeys the orders of authority, specifically those of Dame Primus.
Suzy is really over two thousand years old, but takes on the shape of a 12 year old girl. She wears a top hat and very raggedy clothes.
Suzy is reckless, adventurous, and tomboyish. She does not like to be kept away from action and will often bend or break the rules in order to find some. She is described as a ragamuffin, acting rambunctiously and often using English slang. Although, in Drowned Wednesday she is forced to act as a proper lady for as long as she is on the Border Sea as a condition of being allowed to join Arthur — causing Arthur to believe that she had been washed between the ears (brainwashed) — she circumvents this problem by acting her normal self once underneath the water (since she agreed to be polite and proper on the Sea but not under it).
Suzy's real name is Suzanna Dyer. She was born and raised in England during the Black Death, as detailed by events in Mister Monday. Her father is Jack Dyer, and she mentions her mother and a brother in Superior Saturday.
Suzy is very loyal, especially to Arthur. She is brave, always facing challenges that come her way and making sure she helps her friends. She has the mind of a child (probably due to the process of washing between the ears) despite being centuries old, and will sometimes act immature like one.
Towards the end of Sir Thursday, Suzy disappears when the Piper kidnaps her, Fred (Arthur's friend from the Army) and several other Piper's Children with his Pipes. At the end of Sir Thursday, the whereabouts of the two children are unknown. Shortly into Lady Friday, the two reappear, but are constrained via a sorcerous tattoo that chokes them if they disobey a direct order, or discuss doing so. Although reluctant to use the Keys, Arthur uses the Fourth Key to release them from the Piper's bonds. In Superior Saturday Arthur and Suzy grow closer. Suzy has shown to be jealous of Leaf, expressing this when Arthur gave Leaf The Mariner's Medallion.
As of Superior Saturday, Suzy begins addressing herself as General Turquoise Blue, having her own troop of Piper's Children in the Army (named Suzy's Raiders).
At the end of Lord Sunday, she claims the position of the new Lady Sunday, as well as requesting to "grow up a bit, I'm nearly two thousand years old!", which results in her becoming older and possibly more beautiful (certainly passable by her own standards, judging by her reaction).