Shilo is pale and slender, reinforcing the image of fragility her father has impressed upon her. She is bald, but wears a long black wig, parted in the middle. She has a Victorian gothic fashion sense, with short skirts and ruffles. She is never without her cameo necklace, or the wristband which monitors her blood pressure, reminds her to take her medicine, and is used to make phone calls.
Shilo's mother, Marni, became ill while pregnant with her. In Nathan's search to find a cure for the disease, he accidentally mixed in a poison, planted by Rotti Largo, with the medicine, resulting in Marni's death.
With Marni beyond help, Nathan performed an emergency surgery to save Shilo. Nathan told Shilo that she had a blood disease that she inherited from her late mother, telling her that it was the disease that killed Marni.
She was kept in her bedroom by her dad and was forced to take medicine for the disease sometimes during the day. Every now and then, she would put on a gas mask and sneak out of the house to visit Marni's tomb.
One day, Shilo chased a glowing blue bug out into the graveyard,and there she met Graverobber, who was in the process of collecting Zydrate from bodies. When they are discovered by the GeneCops, she follows Graverobber into a broken tomb, which Graverobber broke into, and she is pulled out of seconds later by the GeneCops. As the Repoman appears and sends them off, Shilo passes out.
Upon waking up in her own bedroom, Nathan pretends not to believe her when she says what happened, telling her that it was merely a dream. He tells her to take her medicine and leaves. Shilo laments her captivity and curses her mother for passing the 'disease' onto her ("Infected").
Later on, Rotti Largo calls her, claiming that he might be able to help her. He tells her to meet him at her mother's tomb. She was, upon arrival, dragged out of the tomb by Rotti's henchwomen and thrown into the back of his limo. Though hesitant, she agrees to accompany him to the Italian Renaissance Fair in Sanitarium Square.
Here, Shilo meets Blind Mag, a singer she adores. She watches the ribbon-cutting ceremony, and is then dragged into an unused tent by Rotti's henchwomen. Nathan calls when his watch tells him that Shilo has yet to take her medication, and she narrowly deters him from going home right then and there.
Shilo is rescued by Graverobber who takes her to an alley where Zydrate addicts hang out ("Zydrate Anatomy"). There she discovers that Amber Sweet is a Zydrate addict; it is Amber that informs her about Mag's contract with GeneCo: If Mag retires from singing, if she refuses to promote GeneCo any more, her eyes will be subject to repossession. When GeneCops flood the alley to retrieve Amber, Shilo and Graverobber escape, and Shilo returns home.
Some time later, Mag visits Shilo when she is home alone and reveals that she is Shilo's godmother ("Chase the Morning"). Nathan arrives home and forces Mag to leave, in spite of Shilo's protests ("Everyone's a Composer"). Shilo begs Nathan to save Mag from the Repoman, and Nathan angrily tells her to stay out of it; there are things in life beyond control, and this is one of them ("What Chance Has a Seventeen Year-Old Girl?")Shilo becomes angry, and proclaims that she is no longer a child. She's tired of being dragged down by Nathan, and by Marni's memory ("Seventeen"). At the end of the song, Nathan slaps her across the face, and she passes out. As she sleeps, a call from Rotti comes, and Nathan learns that Rotti's been in contact with Shilo.
He leaves, and later on, Shilo sneaks out of the house and is driven to the Genetic Opera by Rotti's driver ("At the Opera Tonight"). Upon arriving at the Opera, Shilo learns Rotti's terms: She must capture the 'rogue' Repoman, by using herself as bait.
When the Repoman enters the room, Shilo attacks him with a shovel and learns that he is, in fact, Nathan. At this time, it is shown on the TV screen that Mag is dead; it is unclear from the lyrics, but Shilo seems to believe that Nathan is responsible for Mag's death. She is furious with his deception ("Let the Monster Rise"), and storms out of the room and down to the stage.
By the time Shilo reaches the stage, Nathan is already there with Rotti, Luigi and Pavi. Luigi attacks Nathan, and the curtain rolls open for the audience to see. Rotti and his sons expose all of Nathan's secrets, including that her 'blood disease' was caused by the medication provided by her father. Nathan did this to keep her from the world outside her window.
Rotti gives Shilo a gun, and encourages her to kill Nathan; If she does, he will leave GeneCo to her when he dies. Shilo refuses, and instead turns the gun on Rotti. Nathan urges her not to make his mistakes, and tells her to make her life into one worthy of remembrance. The lights flicker off, and Rotti rips the gun from Shilo's hands; he shoots Nathan, and then succumbs to his own terminal illness.
Shilo is left alone onstage with her dying father. They say that they have always loved each other no matter what happened ("Didn't Know I Loved You So Much"). Nathan dies, and Shilo mourns before leaving the opera ("Genetic Emancipation").
Having been trapped inside for most of her life, Shilo has very conflicting views. She is, on one hand, rebellious, dying to go outside and experience the world she's only ever seen on TV. This is displayed in "Seventeen " and "Infected ".
However, Shilo also displays a great deal of fear of the outdoors. When Rotti has his henchwomen drag Shilo into the limo, Shilo panics, screaming that she can't be outside, and begs Rotti to let her go once the limo starts driving. Later on, during "Chase the Morning ", Shilo is wary of Mag, in spite of idolizing her.
Shilo's feelings for her father change drastically over the course of the story: In "Infected", she loves him, but is bitter towards him for keeping her locked up. This bitterness and outright anger finally comes out in "Seventeen", where she makes a claim for independence and tells Nathan not to treat her like a child.
In "Let the Monster Rise", Shilo's anger is taken even further, turning to hate, when she learns that her father is the Repoman, and (Again, unclear exactly what she believes) seems to believe that Nathan killed Mag. As Rotti exposes Nathan's other lies, Shilo claims that she no longer trusts him.
However, in "I Didn't Know I Loved You So Much", Shilo says that she really does love her father in spite of everything, and weeps upon his death.
Though Marni died at Shilo's birth and therefore never knew Shilo, Shilo initially harbors considerable resentment towards Marni: In "Infected", she outright blames Marni for passing down the 'blood disease' to Shilo. But in "Chase the Morning", Shilo looks at the hologram of Marni with something like longing, indicating that she might not be as bitter towards Marni as one might think.
Shilo's room, upon examination, is covered in pictures of Blind Mag. She idolizes her, and is ecstatic when she finally meets Mag at the Italian Renaissance Fair. However, when Mag actually turns up to Shilo's house later on in "Chase the Morning", Shilo is wary about letting her inside; and once she does, she keeps her distance.
Upon learning that Mag is her godmother and knowing what fate lies in store for her, Shilo becomes panicked and tries to find a way to save Mag. Later on, she is deeply saddened when she sees that Mag is dead.
Upon their first meeting, Rotti charms Shilo and promises her a cure for her disease, a key to the outside world that Shilo has been yearning for. Shilo buys into this deception right up until the end, when Rotti demands that she kill her father in exchange for the cure and GeneCo.
When Graverobber and Shilo first meet in the graveyard, she seems initially horrified by him and his job. Later on, when he finds her in the tent, she becomes irritated with him, telling him to leave before he gets her into trouble. He then helps her escape and, unwittingly, leads her to the information on Mag's contract. When they part ways at Marni's tomb, he waves goodbye. There is very little concrete information about how she regards Graverobber at the end of the story.
- Although depicted as rivals, Shilo and Amber share many similarities:
- Both their mothers were killed by Rotti.
- Both love music.
- Both have a complicated relationship with their fathers.
- Both witnessed their fathers' deaths.
- Both have black wigs.
- Originally, Shilo's wig was intended to be made from her mother's hair, bringing new meaning to Blind Mag's line in Chase the Morning: "You have your mother's eyes, her hair."
- During Tao of Mag , a crucifix can be seen tattooed on the sole of Shilo's foot. Actress Alexa Vega made the effort to hide this tattoo, though later regretted this decision.