The night was cold, freezing almost. It was snowing. Just a little bit drifting lazily down the castle walls, clinging to the wooden window sill and melting to form a trickle of water. It hadn't snowed within the walls since many years before Eren was born. His generation had never seen it.
But Petra had told him that in the north town of Wall Rose, they had spotted the snow clouds drifting in. Perhaps it would scare off the Titans, Eren thought, or perhaps freeze them to death. Hanji had been shocked at his statement, and rushed off to see if she could do an experiment to find out their reactions to snow.
"Is this really the first time you've seen snow?" A voice sounded from the doorway.
Eren hadn't heard the door creak open, but when he turned away from admiring the snow out the window, Corporal Levi was behind him, leaning on the wooden doorframe with his usual bored expression.
"Armin and I read about it in a book. It said it only snowed in the outside world-"
"Reading up on the outside world is banned, Eren."
"We were just kids wanting to explore," Eren murmured, scooting closer to the window as he watched each snowflake with fascination, occasionally reaching a hand out to grab one.
Levi's boots clapped along the floor as he approached Eren, extending a hand to tap his shoulder. "It often snows North of Wall Maria. We sometimes spend a night or two stuck in it when the Recon Corps go out on a mission. It's a pain in the ass."
Eren stretched forward out the window, hanging his arms and torso in the air, trying to catch as many snowdrops on his body as he could before they melted.
"I think it's beautiful, Corporal," he said, his eyes sparkling as he turned to grin at Levi.
He didn't speak up for a moment, but when he did, Levi stood directly behind Eren and wrapped his arms around the boy, pulling him away from the window. "Don't fall out, you shitty brat."
"Sorry," Eren whispered, bringing his hands up to rest on Levi's arms. "Do you see anything else when you go outside the walls?" he asked, turning around in the Corporal's grip. "Like... the sea."
Levi narrowed his eyes but let out a small laugh. All his inhibitions faded away when he was around the brat, and he just couldn't stay angry at him for knowing things he wasn't allowed. "No," he admitted, "but one day we'll all be able to visit the sea."
"When I execute every last Titan!" Eren squealed, fiery determination sparkling behind his bright green eyes.
Huffing, Levi pushed Eren towards the window; albeit gently. "When we execute every last Titan."
Eren hummed an agreement and clenched a fist, holding it out into the forming blizzard. "Yeah! That's a promise."
He left his room that night with little extra conversation: Eren had managed to fall asleep within the next half an hour as he sat at the window, admiring the crystal drops falling. Levi picked him up and tucked him into bed, leaving him with the few words he'd never let anyone else hear.
"And I'll come back to you alive. Every time. That's a promise."