When the inevitable had happened – when the precarious world they had tried to build finally, came crashing down – Raven had been almost, in a sad, sick way, relieved. She had thought, when she was a child, after she had to flee the only home she'd ever known, into a world full of hostility, that she had known fear. She had thought during her pregnancy – those long, anxious months of travelling from place to place, never daring to stay anywhere for more than a few days, always looking over their shoulder for the CIA – that she had known exhaustion. Before the birth, she had even, tentatively, when looking at Azazel's sleeping face on the pillow next to hers, began to think she might know what it was to love.

Karol's birth had changed all of that. From the second he was in the world, it was as if a layer of protective skin had been torn away from her, exposing every nerve to the world in a way she had never known before. It was a revelation to her, he and everything he made her feel was a revelation. So this is love, this inescapable, almost quotidian fact in the pit of her gut and the front of her mind, her world ineluctably reconfigured around a tiny, helpless, sleeping, shitting human being she knew completely and yet didn't understand at all. So this is exhaustion – night after sleepless night, whether he was awake or not, walking the floor to soothe his screams or staring at his tiny chest as if only her watching made it rise and fall. So this, then, is fear, real fear – the constant feeling of exposure, even when he's right there in her arms, as if her beating heart had simply left her chest and was imbued with a will of its own outside her body, going about unprotected in the world.

She hadn't drawn an easy breath since the day he was born. She wondered if this was a function of their uniquely imperiled situation, or if even perfectly normal human mothers felt this way – terrified of their own incompetence, their powerlessness in the face of fate, in the inescapable truth that they could never be really sure that they could keep their child safe.

She watched Azazel rock the baby, coo over him, laugh when Karol burped or blew bubbles or waved ineffectual clawed fists at his father's face, and wondered at how he could be so calm, so relaxed, when the baby was so tiny and fragile, the world so large and full of menace both specific and unknown. Her own nerves had been flayed raw, scoured by a bone-deep need for another that seemed too huge and hungry for the Hallmark name of 'love'. What she needed from Karol she couldn't precisely say, but it was more than just his happiness. She remembering what Charles, in one of his endless lectures about genetics, had once told her about pregnant cats: that if they felt threatened, they would often reabsorb their unborn kittens, the tiny bones melting back into their mother's flesh, until circumstances were more amenable. She dreamt sometimes of eating Karolek, tenderly, with infinite gentleness, sucking mouthfuls of his soft flesh down like pudding while he gurgled happily. Se would wake from these dreams on her feet, halfway to his cot, her breath ragged until she saw him there, safe and whole.

They kept moving. All thoughts of the Brotherhood, the war, even of freeing Erik were put indefinitely on hold, their every move subordinated to Raven's overpowering need to protect her child. For over a year, they traveled randomly, never staying in the same country twice. But their frenzied pace began to slow eventually. Although Azazel was used to the constant teleporting, seemed to feel no differently in Addis Ababa or Alabama, Raven began to flag after a while, to feel the need for the earth beneath her feet, for time and space to focus on her son. They fell almost without realizing into routines, to find favourite boltholes where she felt a facsimile of safety. They nested in Sao Paulo and Madrid and in East Berlin, big, anonymous cities where they could disappear into the crowds. Raven's frantic heartbeat began to slow.

Karol started walking early – if walking was the right word for what he did, swinging up walls and furniture, not seeming to care if he held on with a hand or foot or curling tail. Although he never again showed any signs of the teleporting ability he had evinced in labour, almost killing them both, he began wanting to explore his world, and it broke Raven's heart to refuse him, to pull him away from windows and doors, to make him hide. She yearned for them to be able to walk the streets together like any mother and her young child. And as he grew, her determination to make that dream a reality within his lifetime grew with him.

And it was that determination, that frustration that eventually undid them. The night she decided to take Karolek to the park.

They were in Berlin again. Azazel was asleep. Karol was finally starting to sleep through the night, and they had seized upon the opportunity to tend the flame between them. Passion got precious little priority these days, with the demands of parenthood and the threat of discovery crowding out all other concerns. They made up for lost time, however, and Azazel had fallen into a satiated slumber. Raven, however, remained awake, looking down at the face of her lover as the moonlight turned his red skin blueish-white.

She was glad she had been able to take away his worries for a while. Azazel was not in the least bit given to frets or regrets. But Karolek had had a tantrum that afternoon, when Azazel had refused to hold him up to the window to watch a passing fire engine. Raven had watched from the half-closed door as Azazel tried soothing the boy, tried to reason with him, tried to distract him with one of his many toys (they had to stop acquiring them, it was making moving harder every time). But nothing worked. Karol lay screaming on the rug, fat tears streaking his furry, furious face.

"Nee-naw!" he bellowed. "Want nee-naw!"

Raven sighed. This fascination with sirens was a new and frustrating one, especially in big cities where barely an hour seemed to pass without a fire-engine, and ambulance, a cop car going by. Had it been one of his board-books? She should have thought more when choosing, should have anticipated, tried to choose books that wouldn't draw him to want out more than he already did-

Azazel finally lost patience, slapped his hand on the table top.

"Dostatochno! Ya skazal nyet!"

It was the first time Raven had ever seen him shout at their son. Karol stopped screaming in simple surprise. He lifted his face from the carpet and stared wide-eyed at his father, who was staring back at him with an expression Raven had never seen on his face before – a look of pure pain.

Karolek's bottom lip had begun to wobble as the shock wore off and his wrongs worked within him. But before he could start crying again, Azazel had swept him up in his arms, was walking him back and forth, squeezing him just a bit too hard, kissing his head.

"Tishe teper' moy mal'chik, zamyat' ne plach . Odin den' , ya obeshchayu , odin den'. Papa obeshchayet."

Raven stepped silently into the room. He turned jerkily towards her, and their eyes met over the head of their child in wordless, helpless misery.

Later, after Karol had entirely forgotten the drama and was amusing himself by hanging from the shower rail, the two sat on the bed, holding hands.

"Maybe we should go to the country," Raven suggested. "Deep country, you know? Far away from everyone. Maybe then he could grow up safe, have some freedom."

Azazel shrugged.

"Here, there. Always there are people. And in city, more people, but people do not take time to see, look but not see. In empty places, more see." He sighed heavily, drew a red hand over his face. "These things are always same. Choices, only, but never perfect choice. Always. Before, I know this. I live this. But now…"

Raven winced. She remembered how free he had always seemed to her, how fearless. He was becoming someone else in front of her, someone hounded and harried.

"I know. It's different now. Different for you."

He took her hand again in both of his.

"Is different for us. Everything is." He brought her hand up to his lips, kissed her knuckle absently. "But this is sem'ya, siniy ved'ma."

They heard a metallic crash next door, and tensed, only relaxing when they heard a wild, guilty giggling and the repeated sound of a felled shower rail being banged exuberantly against the tub. Raven gave Azazel a wry smile, rose to go and investigate. But Azazel gripped her hand.

"Ya proshu … proshcheniya."

He said it so quietly she almost thought she'd misheard.

"Sorry? What do you mean, sorry? What have you done?"

He didn't look at her.

"I do this. To him. I make him like this, look like this. If not me for Papa, if someone else, maybe he could be outside. Not hide."

A hole burnt itself in the bottom of Raven's heart. For Azazel of all people to talk like this… she dropped to her knees beside him, took his face in her hands – hard, squeezing, unable to control the rage she felt – not directed at him, but at the whole hateful world that had managed to make this man – her man – feel like he had to apologise for fathering his own child.

"Do not say that, do you understand me? Don't you dare even think it. Don't ever." Azazel opened his mouth, but she cut him off. "Shut up. There is no-one I would rather have as the father of my son. You make him what he is, that's true. And what he is is perfect. Just like you. It's the world that's fucked up, Azazel, not you, and certainly not our son. We can fix that. We will. Do you understand me?"

He shook his head in her hands, but said nothing. What was there, after all, to say?

The rest of the day had passed uneventfully, but a cloud had hung over them, a cloud that had only dispersed temporarily with their lovemaking, a salve but not a healing for the pain they both felt but could not share. Azazel at least had found relief in sleep. But at 2AM, Mystique still could not ignore the hole in her heart, the visceral anger bubbling up out of her chest whenever she thought of that whispered "I'm sorry." Whenever she thought of her son's tear-streaked face.

"The hell with this," she suddenly whispered to herself, and got out of bed, leaned over her son's crib.

"Karolek? Baby, wake up. It's Christmas morning."

It wasn't, of course. But she was giddy with what she had decided to do. Her son blinked sleepily at her, golden eyes so like her own lighting up her world.

"Mam'chka?" he mumbled, confused. This was unprecedented behavior. Usually Papa was the one to instigate crazy games and late night mischief, not Mama. But now Mystique set aside Raven for a while, with her schedules and her rules and her worries.

"Yes, sweetie, now wake up. You and I are going out."

That did it. Karol sat up in bed and crowed. Mystique shushed him.

"Hush now, Papa's sleeping. Don't wake him up."

Karol's face fell.

"Papa don't coming?"

Mystique's heart contracted in pain, but she pushed it aside.

"Not this time, sweetie. One night maybe. Not tonight. Just you and me, OK? Won't that be fun?"

Karol regarded her solemnly, tail flicking – then a grin split his face.

"Let's go, mam'chka!"

And so they did.