Initially only interested in enjoying her new life, Melanie's refusal to fade away as expected forces her to make choices she otherwise would not have, and she slowly develops sympathy for the human characters, eventually acknowledging that they have a right to their own lives, and attempting to sacrifice herself so that Melanie can have her life back.
Melanie is passionately in love with another human, Jared Howe, and shares a strong bond with her brother, Jamie.
Despite initial anger at Wanderer for stealing her life, they gradually become unwilling allies, and finally develop a friendship and a sister-like bond.
Ian befriends Wanderer and gradually falls in love with her, telling her that "[she] is beautiful", not just the body she wears.
He is described as being tall and muscular, with black hair, sapphire blue eyes, and fair skin.
He is described as being muscular and tall, with tan skin, sienna-colored eyes and naturally dark, but sun-bleached hair.
His survival skills are an asset to the group, and he is considered responsible and capable by most other characters, but his rational thinking sometimes becomes a bother to the more sentimental humans.
His behavior and emotions are generally childish, representing an idealized innocence; unlike most characters, he holds no animosity towards Wanderer for stealing his sister's body or life.
He quickly comes to view Wanderer as a substitute sibling, and draws her into the group with his interest in her stories and opinions.
Despite his apparent innocence and naivete, Jamie wants to be treated like an adult; he yearns to go on raids with the others, and is uncomfortable with the coddling he receives when he is injured.
He was one of the first humans to suspect an alien invasion, and thus constructed an elaborate hide-out in caves beneath the Arizona desert.
He believes Wanderer can fit in with the humans, and pushes for this to the point of creating great strain within the group.
He is calm and deliberate in his decision-making, and despite being one of the most welcoming towards Wanderer, nonetheless does not hesitate to explain and justify the humans' perspective to her.
This is later revealed to be due to her insecurity at having failed to subdue her own host, who remembers her name and recovers most of her personality when Terra is finally removed.
Before finding Jodi's body, Kyle despised Wanda and caused a cave-in in the bathroom trying to kill her.
He is shown as deeply affected by his patient's suffering, which in combination with the conditions, places him under great strain; this drives him to alcoholism, such as they can afford.
He is very interested in finding out how the Souls invaded, and their surgical practices, attempting to rescue the victims of the invasion.
He is a man of his word, and is only stopped from killing Wanda like she wanted by Jared's hunting knife at his neck.
Melanie remembers Sharon as a fun and vibrant girl in their childhood but the years have been hard on her and she is now cold and bitter.
Like her mother, Sharon hates Wanderer and obsesses about the threat she poses, sometimes to the point of risking other priorities.
However, the relationship is strained due to Doc's acceptance of Wanderer and Sharon's own prejudice, though she apparently reconciles with him at the end of the book.
Lacey annoys almost everyone with her complaining about life in the caves but is immediately accepted, which slightly upsets the still sometimes shunned Wanderer.
Petals Open to the Moon is eventually removed and placed in cryogenic storage to be shipped to another planet.
Her body is nearly 17 years old at the time she is caught and is small and weak, with pale skin, gray eyes, and wavy blonde hair.
Sunny (Sunlight Passing Through the Ice) — The Soul who inhabits Kyle's girlfriend Jodi's body.
Upon learning that Wanderer could remove souls, Kyle recklessly raced out to find her and brought her back to the caves.
Kathy — Wanderer's Comforter in San Diego, who tries to help Wanda cope with Melanie's resistance and powerful emotions.
Wanda later gives his name as that of a Healer as part of a ruse to take medicine from a Healing facility in Tucson.