So a little birdie told me that Isayama's favorite relationship is Eremin, and trust me, HE'S GOT IT IN SPADES WITH THIS SHIP. 

The sky's colors were beyond anything they had seen in months. The wind swayed in one direction, calm, unfeared, exactly as Armin described it to his friends. Maybe some things could be so pleasant it'd make Eren forget the bitterness of his loss in a world so apart from humanity.

There was not much to do without the likes of Levi or Hange ushering them around. Since activity outside the walls was no longer an option, Sasha and Connie resorted to scavenging within a mile's range of their quarters, where Mikasa and Christa dusted and mopped without envying who got to leave and who didn't. Jean, Eren, and Armin never blanked out, always making sure no one was doing something unjust like lashing out or saying the wrong thing. Every day, there was something to do, but it didn't keep Eren from listening to his inner self.

It had already been a couple of weeks without any question about it. But even under all this uncertainty, after dinners, Armin and Eren would seek the harmless comfort in reading under the moonlight, undisturbed, unfeared, calm, just as Eren felt with his best friend.

"So, did you find anything interesting this week?"

"Hange sent me this binder she found in a library in Trost; it talks about more and more animals every page you go through," the blonde smiled vastly, bringing a load of study onto his lap. "Now, I promised her I would send it back by the end of this week in case the Corps had to use it for any reason, so... maybe we'll just skim through it."

"I could go all night." Eren chuckled a bit. "Under what context do they need it?"

Armin didn't know either, and honestly, he was afraid to ask. "There's no other way to put this but if we keep these records of outside knowledge, we might be accused of trying to..." the boy warded off unlucky feelings.

"Leave the walls?" Eren almost made the blond shudder. He was so bold, yet so tirelessly invested in Armin's ideas that gave him bottles and bottles of hope. "Even if that does happen, we may have to advise the Scouts to come out of their shell with all this AWOL nonsense. You can't trust any book with words, let alone pictures nowadays, can you?" he threw slight gloom.

"Oh, Eren," his buoyant friend gave en eye-roll as Eren had exaggerated. "Do you want to read it with me or not?"

The brunet couldn't resist, even with crossed arms, knowing that Armin could confront his dismissiveness any time he wanted. "Yes! But not too fast!"

"Mhm!" Armin nodded, stationing the book between them and flipping to the author's note. "It says that this book might have been evaluated at a later date or checked for inaccuracies by other people who traveled beyond the walls. Look," he pointed at side notes, "Some articles here were also recorded by actual soldiers and MPs who were trying to build a new sort of scientific industry." the blond read in fascination. "A secret society within the walls."

"So this book was somehow all false at one point?"

"Well, you have to remember that evolution is on a constant shift, and nature always has to have a balance. To do so, the world is constantly changing and reshaping itself to be the best it can be." the blond affirmed, "Because of that, scientists on the run take what they can get." he smiled lightly, "They don't mention that in books."

"It must take a lifetime to explore this much if it means on a never-ending marathon of... nature and stuff." Eren mused.

"Us humans assume a lot of things. It's part of our existence, Eren. And for this book to jump to conclusions about nature, then correct itself continuously, is incredible. Up until now, when we think about evolution, we see the mistakes that allowed for even more discoveries to be made. It's the way the scientific method works."

Armin turned to the following page, running through photographs and attached documents on the side. Eren immediately picked up on the nostalgia sprouting between the two of them; when the days were slow, and they would meet by the river to talk about some big idea that would rock the world. If this book meant endless chatter, he wished he could have sat around for the rest of his life.

"I can't believe there are so many sea creatures that I haven't read about, so many tall animals, wild beasts, friendly, gentle beasts. Beasts that could be superior to a titan!" the blond speculated the next few pages with Eren, his complexion in total awe. "Isn't this amazing, Eren? Oh, there is so much to learn."

Eren gave a smile full of contentment, "It's tempting."

Armin beamed at the next couple of pages, "What do you think about seahorses mating for life? Or what about the fact that pufferfish have the most amazing way of showing their love with artistic abilities?"

"What does that even look like? Does that mean any two creatures mate without consequence? That sounds... like overpopulation." Eren raised a brow.

"I don't know, I wish I could tell you." Armin flipped the page, "It looks like we're heading into the deeper parts of nature, Eren." then he gestured to more attached pictures and a title above them, "Relationships... of the earth."

"That's pretty vague." the brunet grimaced. "Please don't tell me it's mating again. That kind of made me sick, Armin."

He laughed of amusement, "You don't sound sick."

Eren sighed, trying to obtain a sense of strength since he felt entirely beaten by his friend who had gone with a gutsy route to doing all this research. "Go ahead."

Ten chapters later, the two had gone weary over each other, shutting their eyes and leaning into one another without any acknowledgment of what they were doing. Luckily they were plopped down over a smooth surface, heads bending in, and Eren almost burying his face in the crook of Armin's neck. Somewhat of a giggle came faintly from the blond in feeling this irksome but warm movement. Eren stifled a laugh and welcomed the blond's head over his shoulder.

He decided to read aloud and help pass the time, stopping at a new word every few seconds for curt pronunciation from Armin, only to receive gentle murmurs. 

"Competition..." Eren continued, "When two organisms use the same resources, both are harmed. Armin... you don't think that maybe this small vacation out here with each other is doing us damage? Are you and I... hurting each other in the same way?"

The blond shook his head. "No." he cajoled, "There is no harm in sitting here and reading."

"So if there's no harm being done, then what kind of relationship do we have according to this?" Nothing rang more desperate to Eren than finding out what he meant to Armin, and nothing came close to the wistfulness Eren felt in laying there beside him.

Armin gave a small motion with his finger to turn the page. "Keep reading, Eren..."

"You think we'll find out?" the male crooned, his voice openly warm and indulgent.

The blond's features softened; he hadn't felt so giddy in just hearing a million questions from Eren. After seizing the look across his friend's eyes, he pinched the corner of the sheet and flipped to the next. "Commensalism... organisms are unaffected." the brunet rejoined, "Parasitism... one organism takes advantage of another organism adversely. That might sum up titans."

He saw where Eren was pointing, and even though illustrations of examples showed titans, he thought otherwise, "No... this is wrong..."

"Huh?"

"There's no end goal for titans, which means there is no need for consuming humans. Predation suggests the opposite; one organism consumes another organism, but not for sport, for energy to keep them nourished. You see the difference?"

"I do now." Eren agreed.

Armin burrowed his cheek into the width of Eren's shoulder, making the brunet's chest sting with joy. "We're getting there." he turned the page with Eren's narration, "Mutualism; when both organisms benefit." the male stared blankly, "That's it?"

The blond gave a brief chuckle, "You sound disappointed. What do you think there is to it?"

"Maybe there's slips and slides to the relationship, or maybe there's something they can't agree on. There has to be something that keeps things from being mutual." Eren carped, "Is nature... really that in sync?"

"Eren, even people who oppose each other are in sync. Look at you and Mikasa; somehow, some way, you still work together regardless of your distaste in her." Armin touted.

"Do me a favor and leave her out of this. She babies me. Nobody benefits from that." Eren retorted.

The blond sighed, "Eren, it's just an example."

"Yeah... but I'd prefer having you and I as an example for mutualism, that's all." the brunet shrugged, leaving Armin with something to think about. "You're perfect, and I'm not... and that's what makes it a balance."

Armin gave a shy laugh, laying his hand over Eren's and placing his other hand over the brunet's cheek. "You and I are anything but perfect; you have this monstrous power, and I'm right behind you, even when things get rough, but you and I have been made broken to stay unbroken... that's what makes it mutual."