"We're not fit to bear the weight of an angel," River insisted, turning from the railing. "This ship could fly apart under those footsteps."

"It's okay, River," Kaylee replied, casting a curious look first at the slender girl who hovered by the upper railing, lingering by the steps to the cargo hold, then she looked down at their latest passenger, a man taller than Mal with broad shoulders and dark hair and eyes so serious, bearing a weight older even than the eyes of the veterans she lived with. "It's just a new passenger. He's a man, only a man."

"He's made his own way between the stars," she whispered, then turned away graceful as the first step of a dance as the man set his first foot on the stair to the upper level. "He remembers, he knows. He saw the Earth when she was green." River scurried away with an overwhelmed look on her face.

Kaylee turned back and lounged against the railing, giving the man a thorough once-over. If it weren't for her Simon there would be something awful tempting there, enough to entice a girl to try, until he looked up and met a body's eyes. There was a disturbing depth to the serious surface, something uncomfortable to look at. Like staring at the sun, one could only look so long before they had to find someplace else to set their peepers.

The man muttered something as he passed her, following Zoe to the guest corridor. Kaylee frowned and wondered if it weren't time to get her ears checked.

I'm no angel, she thought he'd said, but there was no way he could've heard River's whisper, not from all the way down there. Not no way, if he was a man.

It was a short leap from Pallas to Hyperion and they had legitimate cargo for once, which had been Mal's reasoning in taking on a passenger. Though only one person, he'd paid a sum that made River's head throb to think it. She tiptoed around the new additions to the ship, both cargo and the man, who called himself Kalel. His head teemed with more thoughts than even those that crowded her and she was at once terrified of and intrigued by him.

"How can you bear it?" she whispered, pressed full-length against the floor of an upper-level duct, a hidey-hole she used that not even Kaylee who knew every corner of the ship had sussed out yet.

Through multiple layers of steel and industrial-grade polyurethane his head turned and she gasped. He heard her question, and his piercing eyes looked right through her. "Practice," he whispered back, and she heard. "Focus."

More than an answer, the words were an injunction and River drew back, stung.

They orbited through their paces on the ship, a sun and planet that would never touch, but held whole conversations. No one wondered why River talked to herself; it was her established habit. No one heard Kalel talking to himself, but he didn't.

He talked to her.

"You are a whole person," he told her earnestly, when she sobbed and shook and the pieces wouldn't stay down. "You have it inside of you, it's all there. You are human, you are a girl, you have all the parts of sanity."

"They won't fit," she sobbed from a level and three corridors away and Simon stroked her hair as she spasmed and heaved. "I can't make them fit and stay together, they fly apart, they come up."

"Try keeping the whole universe from colliding with you," he said, wry, and the sense of his scope shocked River into silence.

"Why can't you fly there?" she asked him one night when she was in her bunk and he half a ship away, in the middle of the night while everyone else slept. Everyone, that was, except Mal who sat in the kitchen with a mug between his hands that might have more Irish than coffee. River knew that Kalel was an angel the way she knew Mal sat up late at night with his ghosts because they plagued her too and he thought of Inara and formed questions he didn't dare repeat to the Companion's face. Honesty was the problem, River thought, but only for her because she was the only one who knew what they were all saying inside. Everyone slept but for Mal at that moment, and herself, because dreams brought nightmares, and Kalel, who didn't sleep. "To the place you go, why do you even need our ship?"

"I need a yellow sun," Kalel told her. "Out here in the beltway there's a lot of red dwarfs."

"I see," River said with a nod, and it made perfect sense, she did see. She could read the structure of his chromosomes as easily as he read her body language, and she saw the set-up for energy exchange, a body process far more efficient than human.

She didn't ask where he was going, because she already knew in more ways than the obvious. He didn't ask what she was going to do, because he was too polite to state what they both knew; there was more than one path leading from here into forever. She couldn't bear to be near him, because his heat was scorching and she walked the line of balance precarious as it was. But she watched his calm and alternated between envy and awe.

"I can't," she said, clinging to a doorway as if it were the only anchor to sanity in the deep of her madness. Somewhere nearby she sensed Simon trying to pry her fingers loose, bringing his intentions of the infirmary and possibly another shot, and she clung harder.

"You must," he told her, adamant blue eyes turning in her direction. "Or you will hurt them all, River, one by one. When you're not yourself, you don't know. When you are, you try to fit in too much all at once."

"I can't," she said again, and turned her face away from the thousand-yard stare that could penetrate everything, even the skin and bone surrounding her, peering into her brain, eyeing the scrambled electricity that made up her thought-parts. "They broke it and I can't sort out the rest."

"Find your center," he told her, and looked away. She didn't have to see his face to know it was serene, the same way she didn't need to be in the room to know when he looked at her. "When you find that, the rest will fall into place. You will become who you truly are."

That one puzzled her, made her think, and distracted her from resistance until Simon pried her fingers from their clutch-hold and he carried her off without a fight.

For River, the center did not hold. Things had fallen apart too long ago.