It's not the memories you make, it's the spaces in between that are most important.

Peter wakes to find Olivia standing by the bedroom window, light from a far-off streetlight falling softly on the planes of her cheeks. She's resting her head against the window frame and her breath has fogged up the glass. Her shoulders are hunched, and with her arms tucked around herself and her feet lost beneath the cuffs of her borrowed pajamas, she looks both impossibly young, and impossibly old at the same time. It's one of the very few times she's ever seemed fragile to him.

"Go back to sleep Peter," she tells him softly. Her eyes are closed, but she knew he was watching her. It should seem eerie, but it isn't. They've just always been in tune that way; he's the baseline to her melody, both of them beating at three-fourths time.

But he won't. Her side of the bed is cold and his body misses the press of hers. If that makes him greedy, then so be it. She gives so much of herself to her job, to strangers who need an unwilling hero. Is it so wrong of him to want to keep something of her for himself?

The orangey-pink glow from the high pressure sodium light makes her skin seem sallow, pale, like she hasn't slept at all. "What's up?" he asks.

"It's nothing." She turns her head so her cheek is pressed against the window pane. Then after a while, and because they're still working at this trust thing and he knows she's afraid she might be shutting him out, "My head hurts."

"I'll get you something. Come back to bed." He flips back the covers and reaches for the pair of jeans he'd kicked under the edge of the bed. There's a subtle shift of light and shadows as she pulls herself in tighter.

"I already did."

He's slightly alarmed. He does share the house with Walter, after all. "Not from the medicine cabinet."

"It said 'Tylenol' on the pills." A slight twitch at the corner of her mouth. "I checked."

He makes a mental note to check the expiry date in the morning. "Is it helping much?"

She tips an open hand back and forth in a 'comme-ci, comme-ca' motion. From the way she's propping up the window frame, Peter wonders if she might have been better off with one of Walter's mystery concoctions. He brushes the back of his hand over her cheek, then her brow, but she's not feverish. She leans into his touch ever so slightly, and something inside him thrills; he's still always afraid that she might pull away. Once bitten, twice shy, they say.

"It's more like my head is… " she stumbles over the word. He watches her brow crease as she wills neurons to fire and make a connection. "Platzen," she says finally with an apologetic lift of her shoulders. "Like there's no room for me in there."

"Bursting?" he supplies. He's never heard her speak German before, but he likes the way the syllables roll off her tongue. On any other night, he might ask her to do it again, but he's picked up on her frustration.

She nods slightly. "Yeah, that." Peter has a sudden image of Olivia wandering around the lab, muttering mnemonics to herself. It's not pretty picture. He shakes it away and shuffles a step closer to her with a loud and very frustrated sigh. She leans back into the shadows and meets him halfway, slides her arms around his waist, and hooks her thumbs into the belt loop at the back of his jeans. She's wound so tight that her shoulders feel like marble under his palms. The groan she lets out as his fingers work at the knots takes the edge off the chill he feels in the air.

If he's learned one thing from Walter in the last couple of years, it's that the human brain is plastic, malleable. Capable of rewiring itself if there's a short in the circuitry. Of all the organs that make up the human body, the brain is probably the most elegant, the most resilient.

And the most devastating when it fails.

It doesn't necessarily mean she's damaged, he reminds himself. Faulty word associations, on their own, could mean nothing more than her mind just needs rest. People were not designed with the need to parse more than one consciousness, more than one set of memories at a time, let alone three or four. Peter can see that each person who's taken up residence in Olivia, no matter how briefly, has left something of themselves behind, something as indelible as the ink now on the back of her neck.

Some days he wishes he could have known her before all this began, before John and Nick, and that other version of herself. Before Bell invited himself in without knocking, hung curtains and poured himself some tea. There isn't a damn thing he can do to help her that doesn't potentially involve hypnotics or psychotropics and a heavy dose of Walter, but at least he'd have a baseline for when things went sideways.

He has no idea how she even sorts all these people all out.

She's starting to feel heavier in his arms and he thinks she might have fallen asleep right where they're standing. But then her breath is warm as it tickles his neck. "You know," she says so softly that he almost writes it off as his imagination and those quiet sounds she makes when she sleeps. "I wish they'd ask first. Just once." He stiffens, and then adds 'mind-reading' to the list of talents she underplays. But that's really all about perception, isn't it? Vibrating on the same wavelength is a question of shared experience. It's a trail of thought he turns his back on for tonight.

He pulls back slightly as she says, "It's important. I'd probably say yes." Her arms tighten around him. "Just, some kind of warning would be nice." She sounds so lost in the dark.

And this, he thinks, is as good a reminder as any of how much she needs him. Or maybe not him, precisely, but an advocate of sorts. Somebody to put the brakes on and call for a sanity check before they all plunge head-long over that metaphorical cliff. Because if Olivia sees nothing wrong with inviting multiple beings to invade her consciousness, treats it like it's her duty to allow them to use her body in the service to the greater good...

"Olivia." He sighs again, heavily, and feels her shift, tense slightly. Bracing herself for an argument.

There's a sudden electronic burp from the bedside table and they turn as one in time to catch the splash of the LED's illuminating the display on the modified baby monitor. Peter leans his forehead against hers. "Walter alarm," he says, and they listen to him hum a forlorn version of The Impossible Dream with the clatter of plates and the closing of the pantry door as accompaniment.

"Don Quixote?" Olivia asks, and Peter feels her shoulders shake once or twice with an amusement he doesn't quite share. He doesn't appreciate the irony, not tonight. There is a staticky sort of silence for a while, and then the clatter of a plate landing in the sink. Peter decides that there's no need to investigate this time.

And suddenly, he's tired. Olivia leans heavily against him again and all he wants to do is lie down, to have her rest her head against his shoulder and drape her leg across his so her bare ankle touches his shin. He wants to run his fingers through her loose hair until his eyelids are heavy and everything outside the four walls of his bedroom are like memories of a lucid dream. He wants to keep her all to himself for just a little while longer, before the world comes crashing back in demanding her attention.

He supposes that makes him no different than anybody else who's asked so much of her lately. He hopes his motives are a little nobler.

He straightens. She's blinking owlishly at him, probably just as weary as he is. He holds out a hand. "Olivia," he asks, because nobody else has bothered to request her permission as of late, "would you like to come back to bed with me?"

She takes his hand and he feels the soft brush of her lips across his knuckles before she tugs him away from the window. "I'd like that very much."

And so they do.