Batman Can Breathe in Space: Towards the end of the series, she and Blake have their bodies altered to the point that they are able to walk through outer space nude.
Chemically-Induced Insanity: In the opening of the series, Sparta has spent several years of her life being drugged into oblivion by the Free Spirit.
Creepy Good: By the end of the series, Sparta has altered her own body so drastically that she no longer needs clothes, produces mucous from her armpits, and speaks in a Starfish Language. Her still human companions find her disturbing as hell, even as she works to protect them from Nemo.
Cult Defector: Sparta grew up in the Free Spirit, a transhumanist cult that believed her to be The Chosen One. She later got free, and spends the first half of the series fighting to wipe out the Free Spirit's operatives.
Descent into Addiction: Sparta starts taking various pharmaceuticals in an attempt to counteract the drugs that erased part of her memories. Instead, she ends up severely addicted to one of the drugs, and by the end of the book, she's caused such severe damage to her own brain from drug abuse that she loses her enhanced perception abilities.
Do Not Call Me "Paul": Sparta's spent a lot of time and effort creating her identity as "Ellen Troy", so of course she doesn't appreciate it when Blake shows up and starts calling her by her birth name, Linda.
Female Gaze: In the last book, she spends some time admiring Blake's naked body as he recovers from the gill-implantation surgery.
First-Episode Resurrection: Of a sort. The first book opens with Sparta locked up in a mental hospital, unable to remember anything. Her doctor finally decides to restore her memory.
Go Mad from the Isolation: In the first book, Sparta is described as struggling to avoid crying herself to sleep during the years that she spends training to become a Space Board Inspector, because she's horribly lonely but also afraid that socializing might cause her to expose something about her past. In the fourth book, she suffers a nervous breakdown after a combination of prolonged isolation from others and a steadily-worsening drug habit.
The Grotesque: After altering herself so that she can thrive on Amalthea, Sparta looks and acts increasingly less human.
Hollywood Hacking: Done extremely weirdly in this series. Sparta is able to hack computer systems using electronic spines underneath her fingernails. These pick up electronic signals from whatever she's hacking, which are relayed to the sensory areas of her brain, which translate the data into sights and smells. She can also send commands through the spines.
Innocent Fanservice Girl: Towards the end of the series, she and Blake stop wearing clothes, having been physically altered to the point where they no longer need them. Some of her human companions find this unnerving.
Lonely Bachelor Pad: Whenever Sparta is on her own for extended periods of time, her dwellings become quite... Spartan. It's especially pronounced in the fourth book, when she develops a particularly bad drug addiction that causes her to spend a lot of time in a stupor.
Ms. Fanservice: Towards the end of the fifth book, Sparta abandons her clothes and spends the rest of the book swimming nude around the world-ship.
The Ophelia: Sparta at the beginning of the series is a barely-coherent mess, the result of the Free Spirit's machinations. She gets better, though.
Outfit Decoy: In Volume 5, as she runs from Nemo's attempt to kill her in an underwater labyrinth, she strips off her spacesuit and leaves it floating in the corridor behind her; it's bulky and buoyant enough that Nemo is unable to tell that it's empty until he gets in close.
Pay Evil unto Evil: Sparta's brutal murder of Stig, the brain-damaged superchimp. On the one hand, he was severely brain-damaged and for all we know, he just thought he was protecting his beloved mistress. On the other hand, he was fully prepared to kill Sparta.
Posthuman Nudism: In the final two books, She and Blake radically alter their own bodies to live aboard a massive world-ship with an aquatic environment, and consequently, they no longer need proper clothing to stay warm, instead coating their nude bodies in slime.
Skinny Dipping: After the modifications done to her body, she spends much of the fifth book swimming nude in the world-ship.
Smart People Play Chess: Her ability to win at chess early in the first book is one of the few signs that the Free Spirit's efforts to wipe her memory haven't completely succeeded.
Starting a New Life: In the first book, Sparta spends something like two years setting up a new life for herself as "Ellen Troy" after escaping from a mental hospital.
Weak, but Skilled: Sparta is not especially strong (and in fact, the first book suggests that her enhanced senses actually compromise her endurance), but her ability to learn quickly does extend to martial arts.
What Have I Become?: Linda Nagy was transformed against her will into Sparta, the intended "prophet" of the Free Spirit. Throughout the series, she questions whether or not she's still human.
Blake Refield
Asian Speekee Engrish: Played with in the fifth book. Blake disguises himself as an Asian (which isn't that improbable, because his mother is Chinese) and tries to get a meeting with Luke Lim, a banker on Ganymede. Lim sees through the ruse and tries to ward Blake off by pretending to speak Engrish. Blake isn't fooled by this.
Batman Can Breathe in Space: Towards the end of the series, he and Sparta have their bodies altered to the point that they are able to walk through outer space nude.
Enslaved Tongue: One book sees Blake injected with a drug that's intended to work as a truth serum by making him unable to stop talking. He manages to escape his captors, but spends the whole night rambling on about random topics until the serum finally wears off.
Posthuman Nudism: In the final two books, he and Sparta radically alter their own bodies to live aboard a massive world-ship with an aquatic environment, and consequently, they no longer need proper clothing to stay warm, instead coating their nude bodies in slime.
Training from Hell: Blake's initiation into the Free Spirit entails running through a massive fire, swimming through an underwater labyrinth, scaling a wall, and skydiving without a parachute.
Useless Boyfriend: Averted, he's smart enough that the Commander doesn't mind Ellen Troy bringing him along.
