A few weeks after they move in together, Levi starts having nightmares.
He is very particular about not waking Eren, and since the kid sleeps like a rock, it's not too hard to hide at first. He wakes up slowly, as if he's being sucked out of the dream, and it's worse than jerking awake; when he has to drag himself out of it, he is aware that nothing is real, but his primitive brain insists that it is and carries that horror into consciousness. So he wakes up gasping and sweating, reaches back to grasp Eren's arm just to make sure he's still there and stays awake until he can calm down and get back to sleep. Most nights, he can't. But he gets up early enough for work that Eren never sees him shaking. By the time he does wake up, Levi is already pulling the car out of the driveway.
At first, all he can remember of the dreams are snatches that haunt him throughout the day, so he pauses in the middle of a conversation, temporarily forgets what he's doing, is disorientated while staring at a computer screen for longer than five minutes.
Slowly, he remembers. If he focuses, he can feel fleeting euphoria and a sensation like flying that always tricks him into thinking that the dream is going to be better than it will. One night he wakes up and can remember up the point where the dread sinks in, although the images are always strangely out of his reach. He wakes up frustrated, angry because all he wants to do is sleep, because people are starting to notice that he's drinking more coffee at work and the shadows under his eyes are too obvious to hide.
Yet he comes home and turns his face away from Eren or attempts stilted conversation and goes to bed early, wakes up when Eren slips into bed and curls an arm over his lover's waist. And there Levi stays, terrified of the same nightmare, until finally he does jerk awake and cry out, and he slaps his hands over his face like he can take it all back.
"Levi."
He's shaking again and his face is hot. His palms are slick with sweat but for once it doesn't bother him because in the dark he can see what's been keeping him awake for days.
"Levi?"
And it's not just sweat, he realises, which makes it worse. He can taste salt on his lips and now that he's aware of it he can't stop, even when he shoves the heels of his hands into his eyes like he can force the tears back into his skull, maybe even erase the dream that's made him sopathetic-
Eren shifts on the bed behind him, fully awake after Levi's idiotic flailing, and leans over him. Even though he keeps his voice low, it's strained with the panic Levi wanted to keep out of it. He wants to tell Eren that it's nothing and he can deal with it, but he knows that if he opens his mouth things will get worse. He's never lost control of himself like this and it terrifies him. He doesn't cry. He's never needed to or felt the urge to, not since he was a child.
But he eventually lets Eren pry his hands away from his face, and Eren doesn't protest when Levi buries his face in the kid's shoulder. His breathing is heavy but at least the tears stop. Still, he clings to Eren as if he'll fade away otherwise. Eren waits for Levi to speak if he wants to, and if he doesn't, he won't push it - but Levi doesn't want to go through that again, when they keep secrets from each other and then stop talking until neither of them can stand it.
When Levi stops shaking, Eren slips out of bed and goes tottering around in the kitchen for a while, deliberately making noise so that Levi knows he's still there. He comes back with a cup and Levi gratefully takes it. He doesn't have the energy to say that he's a grown man and doesn't need warm milk to help him get back to sleep, but he can't deny that it eases his nerves. So he leans on Eren's shoulder, drinks the milk and feels uncomfortable because he is painfully aware of the sweat drying on his skin but he deals with it because his other option is not being able to see Eren and he doesn't want to have an episode in the shower. But by the time Levi sets the empty cup aside, Eren has gone and returned from the bathroom followed by the sound of running water, and Levi follows him. Neither of them say a word and it's better that way when Levi can't trust his voice.
In the shower, when Levi can see everything and be sure that Eren is just as safe as he was when he went to bed earlier. Eren is not hiding any fatal wounds, or coughing up blood. He relaxes a little. He can taste the water, Eren's skin and soap, feel the heat of his skin and his pulse.
"It was about you," he explains, glad Eren is close enough that he doesn't have to make himself heard over the water. Eren leans in, pressing their cheeks together. "You died and I couldn't save you." He sighs because it's the most typical dream in the world and not the first time he's had one like it. But then he reminds himself that usually, the cause of death isn't a giant, and he's never imagined someone he cares about being eaten in front of his eyes. He can't imagine why he would have a dream like that, even this close to his deadlines. His nightmares usually involve more late paperwork than armies of monsters.
Eren holds him and Levi is grateful that he doesn't say something pointless, like point out that he's alive and should stay that way for a good few decades. And if Levi ever described the dream, being told that it was impossible wouldn't make him feel any better. Giants don't walk the earth and devour people, not in the real world. But it had felt real, as if he had spent a whole other life being terrified of and disgusted by them. He had never failed, it seemed, at least until that moment when he watched a monster snatch Eren from the ground as if he were a toy-
Eren- the one holding him up in the shower and reddening in the heat- grunts with pain as Levi digs his fingers into his arms. He realises what he's doing, jumps back and hits his back on the shower dial. They stand there for a second as the hot water begins to run out. If it was up to him, he would leave and go back to bed; but Eren has never been like Levi.
Levi idly wonders if this is what it's like being the younger one when Eren steps out, gets towels and shuts off the water. It's always the other way around with them. Levi makes sure Eren eats something with a vegetable in it. He makes the list of chores so it's one less thing to argue about and he's there when Eren needs someone to hold onto. He feels out of place and clumsy, but maybe it's just time he learned to be looked after.
"I'm tired," he whispers as they're sitting on the edge of the bed, undressed and still slightly damp.
"You could've said you couldn't sleep," Eren grumbles, and Levi manages a tiny smile. "And if you're going to tell me you didn't want to worry me, don't." Eren looks at him, waiting for him to say otherwise, and grimaces. "You're pathetic."
Levi nudges him with an elbow and Eren nudges back and then they're laughing like children and Levi forgets a little of his tiredness as the towels start slipping and he straddles Eren on the bed.
They look at each other, with Levi pinning Eren's wrists by his head, and then they're kissing like they haven't done in forever because Levi's always been too tired and too busy pretending that he's fine, although he always knew Eren could see right through him.
And in the morning they wake up sprawled all over each other with the towels somewhere on the floor. The bedside drawer is still open although neither of them managed to take anything out of it. They laugh about it. And the nightmare doesn't come back.