I really can't talk about Eugene/Sonos without talking about Sarah.
Who is Sarah?
Sara is the natural allegedly natural daugther of Dr. Eugene Talbot who's maternal mother is Aerial Coronel, a mysterious woman who's lineage go as far back as the early days of the American republic from a family witha background of spirit distillers. Dr. Talbot sometimes changes his stories when telling about his wife: sometimes he says she is of Romani descent, sometimes Moorish, Iberian, or Sephardic and cryptically as "of the coexistence". With sometimes love letters written between himself and his wife in Spanish, Ladino, French, Esperanto and curiously, Japanese (Talbot often mentions matrimonial retreats to Japan ever since both having fallen in love with the country during their honeymoon).
Sarah's predisposition is like that of any young woman - with her appearance to being like a young Jennifer Connolley. Her fashion, similar to Connelly's character in the movie Career Opportunities, black jeans and a white tank top with a black denim jacket with a "Lucky 13" bar pin of the now closed Lucky 13 dive bar in San Francisco.
Her predisposition of her personality is positive, cheerful, enduring, although she is strong willed when she has to be and is very sharp witted with sometimes her anger getting the best of her but most of the time she sometimes manages to make her developing silver tongue work. She tries to not lie as much as possible and often has proverbs she likes to live by such as "walk slow and careful", "when in doubt, do nothing", and sometimes, usually when conversations call for it, an admission that "only in the dark does the truth come to light sometimes." She sometimes is good at making jokes with sometimes good timing - laconic one-liners that she sometimes cites as "good enough for writing for an action movie star." Her stupid jokes are when she yells "Rocket Launcher" in the fake Arnold Schwarzenegger Austrian accent used in the video game "Metal Slug" (she'll use this reference only once in the game). Her favorite hobbies are horticulture with a focus on spices, herbs and roots (habaneros, ghost and Carolina Reapers, Cilantro, Dill, Rosemary, Parsley, ginger, turmeric, kava kava) but sometimes manages to make time for citrus planting (Yuzus, Meyer Lemons) . Her favorite trees are the Douglas Fir and Fuji Cherry.
Much like her father she has her stoicism that can sometimes shows her slight changes of personality of that being the avatar of Sonos. In Ascended Form, her name is Polimnia, the Spanish translation for Polyhymnia, named after one of the nine muses responsible of sacred poetry, sacred hymn, dance and eloquence, as well as agriculture and pantomime.
When aspects of her Ascended form, or hints of her "inner self" come out, are usually when very situations arise around her and she starts to feel the ambient situation around her. It's slight and never sudden with only few being able to notice the changes in her. There is a moment in the game where she will have an inexplicable moment where she, at a garden courtyard at night, during a midnight expermient with her father, she begins to float and glow white in front of her father, with her father looking on with a look of expectation but no emotion showing save for his eyes widening slightly. This event will be witnessed by either secondary or tertriary character (NPCs) or a video camera - the melody of the song "Breath Your Name" from SixPence None The Richer could be the source of inspiration for this scene. It's important to have this event as it reveals her nature to what she ultimately she is to serve in spite of her own person and agency: she is to be an avatar, a stand in for Sonos. The reason for this conversion is left a mystery but there is a rhyme to her relationship to her father in spite the death of her humanity has effectively severed blood ties with her father. This makes the continued bond with her father suspect to being an egineered spiritual bond that her father has produced before the activation of The Speculum Machina or Mirror Engine. But there is a mystery because it can be suspected that the bond is also because of her love for her father even beyond death.
Sarah's Job
Sarah is any average early 20-something. She holds a part time job at a deli sandwhich shop, she studies in college focusing on thermonuclear physics. She struggles sometimes with sometimes needing help from her father and her friends. Sometimes it's a source of conversations and banters between herself and her father. But she's often fascinated by the subject because she believes that she can find answers to abstract questions she sometimes struggles to articulate but sometimes, and only when things are serious, she snaps into a mode that can only be described as genius, but when thre's nothing going on, moments of peace, she gradiates back to her usual self.