Acheron
Charon watches her paint his hands incandescent. When she dies - which she often does - all her soul has to do is follow the maps Charon's fingertips trace. He leaves incandescent fingerprints on glass doors (maybe today, she won't be translucent), and feels rigor mortis in her stead.
He brings her back to life almost as often as he rows her across dunes and rivers.
Lethe
Each rebirth is more painful than the last.
She remembers too little, and makes the same mistake of watching Charon sleep every night. She doesn't know that the phosphorescent grass and bloody bandages and his translucence used to be the constellations that seared supernova-bright in her mind.
She remembers too little, and makes the same mistake of burning Charon in her gaze. She could see his kidneys and his lungs, but there was nothing in his ribcage except for broken bones that never set, where the soul was supposed to meet the body.
Phlegethon
Somehow, her hair always seemed singed, smelling of smoke and gunpowder. Wildfire girl and Charon was dry grass. She chopped her hair off, once, and the loose strands sparked and burned their small camp.
"I don't want to burn," she says, but Charon does not believe her.
Witches at the stake burn to live.
Cocytus
Embryonic hands paint her incandescent. She's silent, like a fetus, or an empty womb. Silent, so silent not even death could brush the hair from her face. Only Charon could, but he refrains and chooses to save himself from his translucence. In her fever dreams, she holds his hand and hers and dabs a little incandescence on his right palm.
But she's silent, like a severed umbilical chord, so silent even life could not inflate her lungs.
Only Charon could.
And he does.
Styx
She sleeps with a bottle cap in her mouth and prays to live in the land of the dead.
"Is this enough for my passage across your river?" she asks, handing him the cap, her mouth wide open. He could see the ulcers, the scars, the consequences of yearning to live in the land of the dead, the past, the future, etched in the crevices of her mouth.
"No," he says, "go back to sleep."
She prods him with the bottle cap, clutching her books to her chest. Her eyes tell him that she has sold her ammo for half a book, while he was sleeping, from a passing merchant. He silently takes note of her inventory: Brahmin steak, clean water, eleven and a half books on mythology, a plasma rifle.
She's good as dead.
(And, as always, she's been bad at living.)