Killian's demons are strongest in the daylight. He doesn't have to imagine the slight hesitations, concerned looks, and mistrustful eyes that glance at him before the smiles come. They care about him, he knows that, but he sees his most recent sins etched too clearly in each of them.

Sleep brings blissful oblivion. His dreams—good or bad—faded away in the morning light.

For Emma, the story is different.

# # #

The first time happens about a week after their return from Underbrooke (as Henry liked to call).

It's an ungodly hour when Killian wakes to darkness and an empty bed.

The spot where Emma should be emanates warmth, proof she hasn't been gone long. He almost calls her name, but spies the closed bathroom door and chides himself for worrying over nothing. With an emphatic thump to his pillow, Killian reaches for the embrace of sleep once more. It doesn't come. He thinks it must be Emma's absence at first, but the longer he waits for the solution to that problem, the more pronounced the silence around him becomes.

Propping up on one elbow, Killian eyes the door again, observing the dark shadow underneath the door.

Emma always turns the light on.

He knows he's probably being ridiculous, but he throws back the covers anyways and pads over the bare floor—they really should get a rug—to knock softly on the bathroom door.

"Emma, love, are you alright?"

There's a muffled gasp behind the door.

"Emma?" Silence. Killian grabs the handle, wrenching at it in futility. Locked. In this the week they've lived here, Emma has never locked the bathroom door. The sense of wrong in his gut uncoils, baring pointed teeth. He rattles the handle. "Emma, unlock the door."

Still nothing.

"Swan, unlock the bloody door or I'm breaking it down."

"Don't."

Despite the crack in her voice, relief floods over him at the sound, even as his heart breaks for the pain he hears. She's been crying.

"Go back to bed, Killian," she says, her voice measured again. "I'll be there in a minute."

He knows that voice. He's heard it too often in the last few months. He heard first outside of Granny's when she confessed why she'd been avoiding him. He heard it that day among the stones when she held Merida's heart in her hand. He heard it the day he found her in Regina's room in Camelot.

Emma is afraid.

Not just afraid, verging on panic.

His half of a heart squeezes painfully in his chest, the source of his unease blindingly apparent.

"Emma, let me in please."

A stifled sob and ragged breathing are the only reply he receives. Scenarios flit through his mind and he finds himself fighting panic as well. He presses his palm against the door, tamping down on the feeling lest it feed into whatever Emma feels right now. He wants to break the bloody thing down, just like he threatened—he needs to know that at least physically she is okay—but he can still hear the echo of barely restrained emotion in Emma's voice. Her behavior scares him, but he won't risk scaring her more. Not yet, at least.

"I'm right here, Emma," he says, forehead touching down on the painted white wood, "I'm not going anywhere." He keeps his voice low, soft, falling into the pattern he recalls so well from their weeks in Camelot.

Long minutes tick past. Eventually, Killian sits, leaning back against the wall as he waits.

How did he miss this? Everything that happened had been hard on him, to be sure, but it happened to Emma too. He knows how it felt to have that demon in your head. Knows full well what Emma went through—he inflicted much of it. And here he is, so wrapped up in his own struggle that he overlooked the cracks in her façade. He should have been as focused on Emma in this last week as she had been on him.

How could he have failed her again?

At last, the locked clicks, but the door remains shut. An invitation. Or permission perhaps.

Killian opens the door carefully, bracing himself for any of the dozens of panicked scenarios he devised over that last twenty minutes.

He finds a scene infinitely more heart-breaking.

Emma is curled into a corner where the tub met the wall, arms wrapped tightly around her knees. Grown woman and lost girl exist simultaneously in the slant of the moonlight. He leaves the door open, they have both spent too much time in darkness, as he goes to her and kneels on the cold tile floor. She keeps her forehead pressed against her knees, jerking when Killian runs his hand through her hair.

"Sorry," she mumbles.

"What happened, love?"

"Bad dream."

Shame washes over Killian, the details she left out hanging in the air as full sentences. He pushes the guilt away. Right now, Emma needs him. Allowing remorse to suck him back in would only end with her holding his hand when she needs him to hold hers.

He should ask, he knows, no matter how painful he hearing her nightmare would be to him.

Instead, he pulls her close, waiting patiently until she relaxes into him. It takes far too long for his liking.

"I'm sorry," she says again. "I didn't mean to wake you."

"No no no," he croons. "Don't. Wake me whenever you need to."

# # #

The slamming bathroom door jolts him from oblivion the next night.

Still half asleep, Killlian stumbles after Emma, unsurprised when he tries the door knob and finds it locked. Heart aching, he sits by the door and tries to do with his words what she'd done hours ago by simply lacing her fingers with his. Tonight he waits a long time before Emma unlocks the door and he can't help wondering if she locks the door out of fear of who he'd been. If in the recesses of her mind, some part of her still equates him with the Dark One.

She doesn't flinch though when he crouches next to her or when he lifts her and carries her back to bed. Quite the opposite, in fact. She clings to him with trembling arms, tight enough that he finally gives up returning to his side of the bed and worms his way into the Emma shaped dip already forming on her side.

"I'm sorry," she whispers. "I'm so sorry. I didn't mean to wake you."

"Shh." Killian presses his lips to her forehead. "Don't do that. Don't apologize."

She shakes with sobs as Killian cards his fingers through her hair. One of her hands finds the place above his heart and stays there. He presses his stump against her hand, a gentle reminder that he is there. An hour passes like that, Killian untangling his hand from her hair every so often to wipe away Emma's tears until she looks up at him, an embarrassed smile gracing her lips.

"Sorry to be a both—"

"Last night wasn't a one-time thing."

Emma lets out a slow breath, turning her face into her pillow. "No."

"How long?"

"Since we got back."

A lump rises in Killian's throat. Eight days. This is the eighth night she has woken from these night terrors and battled them on her own in a locked bathroom.

"Were you ever going to tell me?" He is surprised he could get the words around all the frustration, guilt, and grief warring for dominance inside him. Not the place. Not the time.

Emma's silence speaks for her.

"Emma, look at me please." He waits. He waits long enough he thinks she has fallen asleep until she sighs and opens her eyes. And gods, those eyes. He gropes for the words he'd been about to say. "We do this together, Emma Swan." He traces the still wet tears tracks on her cheek with his thumb. "You drive away my demons every day. I will gladly lose a little sleep to help you fight yours."

Emma swallows, pulling him close again. "Please, don't tell anyone."

"Wouldn't dream of it love."

# # #

Killian learns a lot of things in the weeks that follow.

He learns to be a light sleeper. It takes the rest of the week before Emma stops fleeing to the bathroom when she wakes from a night terror, but she stops locking the door after the second night.

He learns to make sure she is awake before he touches her after one night when she mistakes him for one of the demons that haunt her dreams. A shiner decorates his jaw the next morning. Emma's magic cleans up the physical evidence, but he sees the apology in her eyes all the next day.

He learns not to let her resilience fool him. Emma powers through her guilt during the day. The brightness of her smile when she looks at him might erase the shadows under her eyes, but now that he knows they are there, he can't miss them. Small moments get to her occasionally and she never parts from him without an "I love you". Those three words fell so freely from her lips now, like she fears he will forget.

Or perhaps, she fears she might not get another chance to say them. This was Storybrooke after all.

He holds onto to those words though. And to the way she loves to smooth out the furrows in his brow with her fingers. How she squeezes his hand whenever the shadows tried to tug his thoughts away from her. How she pulls him aside at just the right moments to kiss him and ask if he was okay.

She is his strength during the day.

He is her safe place at night.

# # #

By the time she stops seeking safety in the bathroom, Killian learns that what Emma needs isn't always him. He wishes it was. He would jump inside her head and fight the bloody demons all night if it meant Emma could get a decent night's rest. But he can't, he must make do only rub soothing circles over her back as she looks up at him with wild eyes.

"Henry's okay?" she asks for the fourth time, fingers digging into the fabric of his t-shirt

"Yes, love, he's right down the hall."

Emma nods, head falling onto his shoulder. "You're sure?"

He slips out of bed, holding his hand out to her. "Why don't we go see?"

They tiptoe down the hallway, her hand crushing his as they pause at Henry's door.

He leans in so his mouth is a hairsbreadth from her ear. "Are you opening the door, or can I have my hand back?"

She blinks at him, understanding creeping across her features. "Sor—"

He presses his finger to her lips. "Shh, love." The door opens without a sound—Killian makes a mental note to grease the hinges on Henry's door just in case these visits become habit—and checks inside. "Still there," he mouths, stepping back so Emma can see for herself.

Emma leans against the doorframe, eyes scanning Henry's sleeping form before settling on the steady rise and fall of the boy's chest. They stand there for several minutes, Killian's arm wrapped around her waist, before returning to their own room.

"Emma, can I—I need to know…" He trails off, courage failing him. Killian turns his face away, only to be brought back to those green eyes by gentle fingers.

"What, Killian?"

"Is it me?" he asks. "Your dreams…Am I the one…" He closes his eyes, struggling to stay in this moment.

The bed creaks, the mattress springing back as Emma's weight shifts away.

When Killian opens his eyes, she sits at the edge of the bed, kicking her feet out in front of her.

"It's me," she says. "I dream about everything I ever thought about doing as the Dark One…I—" Emma sighs, head sinking. "Every night I rip out someone's heart and crush it while everyone watches. Henry. My parents. You." Emma buries her face in her hands, tipping so far forward she almost falls.

Killian reaches for her, hand resting on her shoulder until she softens and he coaxes her back under the covers with him. Tracing lazy patterns on her shoulder, he waits for her breathing to slow. She smiles into his shoulder as she recognizes the same eight letters she'd traced into the palm of his hand only this morning when a few careless words sent him spiraling toward self-doubt.

"I love you, too," she whispers.

# # #

Despite the lack of sleep, Emma pushes through each day with aplomb. The days that her demons follow her into the daylight are rare and most of Storybrooke remains clueless about her nocturnal demons. Killian suspects Henry knows as the lad found more and more excuses to spend the night at their house. The lad, of course, blames the occurrence on the presence of his infant stepsister.

# # #

"Emma, love, wake up."

She twists away from his touch, still caught up in whatever dream world held her captive. Whispered words escape her lips, unintelligible but desperate. Killian tries again, shaking her shoulder and nearly getting smacked in the process as Emma bolts up right.

"No!" The word rips from her mouth, sharp and ragged and loud. Emma looks at her hands, tears streaming down her face as she flexed her fingers.

"It was just a dream, Emma," Killian says.

Emma jumps, wild eyes meeting his. "No. I have to—my mom—I just—" Emma clambers out of the bed, nearly tripping as the blanket catches around her ankle. Her breath comes in panting gasps, while body shaking as she yanks open the closet door and flicks on the light.

"Tell me what happened," Killian says, following her to the closet and taking her jacket from her.

Emma lunges for the red leather, fingers closing around a sleeve only to recoil. She reels back in the small space, fresh tears welling in her eyes as Emma sank to her knees. Killian drops the jacket, kneeling next to her and trying to pull her into his arms. She pushes him away roughly.

"I did it," she sobs. "It was me. It's my fault."

"Emma, it was just a dream."

He tries, for over an hour, he tries coaxing her out of the closet. She shoves him and screams any time he touches her and he might have been hurt by the fear in her eyes, might have mentally dressed himself down for becoming something she fears subconsciously, if he hadn't recognized that her fear is not of him, but for him.

At last, in desperation, he grabs Emma's talking phone from the bedside table and taps buttons until he gets one of her parents.

A touch of alarm colors the foggy voice that answers the phone. "Emma?" David. Naturally.

"Dave—"

"Hook?" The bleariness in David's voice vanishes. "What happened? What's wrong? Is Emma—"

"She's—Look, sorry to call like this, but—" How does he explain? He knows Emma hadn't mentioned a word of this to her parents. He'd watched her brush off comments about the dark circles under her eyes just yesterday. On the other end, he hears Mary Margaret's voice and remembers why he called. "Listen, mate, can you put your wife on?"

"Not until you tell—"

What sounded like a wrestling contest echoes through the phone, accompanied by hoarse whispering. A moment later, Mary Margaret speaks, "Killian, is everything okay?"

Killian sighs. "Just a moment."

Emma still huddles in the closet, quiet now—too quiet—fingernails digging into her bare knees. She doesn't shy away as Killian crouches beside her, just draws in another struggling breath. Relief floods through him as she looks up at him and not through him.

"It's your mum, love" he says, pressing the phone to her ear.

Her hand automatically comes up, her fingers cradling his.

"Mom?" Her voice cracks on the word and Killian fight the lump rising in his throat. Emma takes a deep breath and then another. "No, I'm...fine. Could you just…talk for a minute?"

# # #

They have good days and bad days. Good nights and bad nights.

What happened changed them. They will never be quite the same and Killian isn't fool enough to expect otherwise, but the good comes more easily and the bad begin to dwindle away. Their demons pushed back into the shadows by the light they cast for each other. Emma no longer apologizes when she wakes him. She still wants to, he can see it in her eyes. Someday, he hopes she truly understands that she doesn't need to.

"Emma? You with me, love?"

Emma nods.

"What do you need?"

Carefully, he tucks her hair behind her ear, gauging the damage this nightmare—the first in over a week—had wrought. Emma leans into his touch, grabbing his hand and pulling his arm around her. Her fingers slip between his as she buries her tear-streaked face against his chest and breathes deeply. Killian presses his lips to her hair.

"I'm right here, love," he says when her other hand touches the scar on his neck. "Everyone's fine. Your parents are fine. Henry's fine. We are all safe." Thanks to you. He keeps the last one to himself as he repeats the words, the band around his chest loosening as her tears slow. Emma makes no attempt to talk, so he keeps murmuring into her hair until she relaxes completely, rolling onto her back as she always does when truly asleep.

Killian sighs. The worst is past for tonight. Tomorrow, they can deal with the bags under both their eyes and the short tempers that consorted with a bad night.

"Sweet dreams, Swan," he says, kissing her temple before settling back in for the night. A few minutes later, he was asleep too.