Eren really wished he had managed to cut that human's fingers off. He really wished he had managed to drown that other one in the tank. He really wished he had killed the one that shoved him in that metal thing. He really wished he wasn't a complete failure that got caught in a net. He really wanted to go home.
After the humans removed him from the tiny cage he almost broke, they moved him into an even smaller one that was not as easy to break. He had already tried, and the nearly broken right hand was proof enough of that.

The humans had left him there the day before and he had seen none of them until that afternoon when one came to pull a net over the surface of the pool to keep Eren from jumping out. Sleep had not come easily that night, and he spent the better part of it nursing his fin and struggling to navigate through the water with only one working fin.
A part of Eren recognized that his reduced physical mobility would have damned him if he had managed to make his escape when he was caught. It would have taken him the rest of the day and most of the night to reach the tribe, and then he, Mikasa, and Armin would have most likely been left behind because Eren would be too slow. He would never allow his own shortcomings to disadvantage his siblings, but they would never consider leaving him behind. His limited mobility would leave the three of them open to shark attacks, and he would never be able to live with himself if Armin of Mikasa got hurt of killed because of him. He ignored that side of himself, refusing to believe that his capture was fortunate in any way. There was strength in numbers, even if they were few. Besides, Eren had always been good in a fight, and he could grudgingly admit that Mikasa was as well. They would do fine on their own. They had before.

After his restless night passed and another human came and lifted the net, Eren had become increasingly curious about what was going on above the surface of the pool. He could feel sound vibrations in the water and occasionally noticed people passing by the pool. No one ever came to Eren's pool, leaving the merman to himself. He resisted the urge to approach the surface, floating near the bottom where it was easy to avoid the rough, abrasive texture of the pool's walls and keep his injured fin out of harm's way. He was slightly grateful for the human's avoidance, preferring to interact with them as little as possible.

The peace wouldn't last for long.

Eventually, a shadow fell over the pool, shading Eren's face from the sunlight that streamed through the bright blue water. It was that bug-eyed human from before, the one he stabbed. It had that creepy look on its face that Eren already knew meant trouble. He watched wearily as the human dragged up a bucket and fished around inside it. It pulled something out and tossed it into the water, warping the water's surface and Eren's view of the human.

The thing floated on the water's surface, glittering brightly as it bobbed along. A smell reached Eren as a few more of the things were tossed in, and it was only the rumbling of his stomach in response that made him realize that he was staring at fish.

Food.

He eyed the human at the surface. It was sitting down now, well away from the water's edge. Eren circled the bottom of the pool, testing his speed. He didn't want to be near the surface if he could help it, but he was hungry, so he would try to reduce the time instead.

Hanji watched in avid interest as the merman circled the bottom of the pool, his movements hampered significantly by his missing fin. He was obviously planning to make a grab for the fish, and Hanji already had a camera rolling, ready to record the moment.

Surly enough, the merman breached the surface, his hands darting out to grasp the fish, his back arching as he quickly curved his body downward to re-enter the water. His tail splashed the water aggressively, flicking water onto Hanji intentionally as he disappeared below the surface. Hanji only giggled, saving the video to the memory card as she tossed more fish into the water.

The merman ignored the new morsels floating on the water and instead gulped down the first three, not even chewing the fish and instead swallowing them down, bones and all. Hanji watched, enraptured, as the merman's neck seemed to expand and swell to accommodate the fish he swallowed down.

The merman made a few more passes at the surface, grabbing up the fish the same way each time, making sure to splash Hanji with water each time. She had made sure to keep away from the edge of the pool, for her own safety, but now that she thought about it, her distance probably made the merman feel safer to approach. She recorded her observations and new hypotheses in her notebook, and just as she tossed the last of her fish in the water, she got a wonderful idea.

Yes, it's perfect, she thought.

Hanji made a show of rising from her spot and stretching, glancing at the merman out of the corner of her eye, who was in turn peering at her with clear suspicion. Hanji had to look away before a smile could break out on her lips.

Can't give it away, can't give it away!

Hanji picked up the bucket and deposited it with the others before checking the rest of the outdoor facility. None of the others were outside today, her plan could go into action immediately. Hanji quickly unlocked and opened the door to the indoor facility, leaving the door wide open. She also 'accidentally' dropped a cleaning rag on the ground near the Merman's pool as she pretended to tidy up the area in case he or anyone else was watching. When she was satisfied her brilliant acting had made the merman lose interest, she pretended to walk back through the doors to the indoor facility, seemingly forgetting to close the door behind her.

She quickly dashed down the hallway and went through the side door, hopping over the fence so that she was back in the outdoor area. Hanji stalked quietly past the merman's pool and wedged herself into a tight space between the wooden fence and the brick wall. No one else knew about her little hiding spot (except Levi, but he avoided her on principle), and it was the perfect place to observe the merman without him spotting her.

"Our meeting is going to be delayed Erwin. Sorry, not sorry," she muttered, settling in to wait for as long as it would take for the merman to make his move.

Eren wasn't the brightest tool in the shed, but he could hardly be blamed for assuming that it would be the perfect time to make an escape, despite the fact that he had no legs and couldn't breathe for very long above water. Even if he could, he wouldn't make it very far, but at the time, these concerns simply became technicalities. Who needs legs?
He did, obviously.

He had been suspicious at first when bug-eyes (that's what he decided to call the human) suddenly became very excited about something, scrambling to tidy up the surface area, most of which he couldn't see due to his lower position in the water. He listened intently for several minutes until silence suddenly befell the area, and that's when Eren knew he was totally alone in this place.

It had been a tentative moment when he stuck his head out of the water and peered over the pool's concrete edge. There wasn't a single human in sight.
It seemed too good to be true, and Eren was tense as he waited for a human to come walking through the open door of the building across from him. None ever did.
Eren's eyes darted about the area once again before he finally grit his teeth and made a go for it.

Hauling his body up out of the pool was far more difficult than it needed to be, but with a missing fin, there wasn't much Eren could do to boost his momentum to give himself the extra push to get his lower body over the edge. After a lot of huffing and puffing and three re-starts, Eren managed to get his entire body onto the concrete. He immediately began feeling the effects of suffocation on his body, and he was quick to snatch up a discarded rag and dip it in the water and drape the wet rag over his gills. The humans had done the same thing yesterday when transporting him, and it seemed to work just fine.

With the breathing problem solved he immediately selected the exit for his desired escape attempt: the wide open doors of the indoor facilities. He hoped that there were no humans in there either, but the chance of that was minimal. That was a problem. If he was caught, they would drag him right back to the pool, and they would probably keep that net over the water to make sure he would never escape again.

He needed a weapon.

An immediate scan of the area yielded no suitable candidates that could at least be broken to form some sort of crude weapon, and Eren was forced to pull his body across the rough concrete to conduct a more thorough search. He eventually got his hands on a metal skewer that had been attached to a pole. It wasn't much, but it would have to do.
Eren soaked his breathing rag in the pool again before he set off, slowly dragging his heavy tail onto the smooth tile of the indoor facility. Eren was still soaked, and the water helped him glide his body over the smooth floor easily.

The building wasn't the same one the human's had carried him out of yesterday. He had been kept in the building on the other side of outdoor area that housed his pool. The building he was in now was most likely some sort of management facility and had less decoration that the other building. The halls were lined with offices and the walls were painted a plain white color, but Eren didn't notice any of that. He noticed door at the end of the hallway that undoubtedly led to the outside. Eren didn't hesitate as he began pulling himself down the narrow hallway. He didn't think about what he would do once he got though those doors. There was only one word on his mind.

Escape.

Levi hadn't wanted to deal with the merman after they finished relocating him. He didn't even want to acknowledge the merman's existence. After he made sure Hanji wouldn't die from her injury, he cleaned up the water trail they had created when they moved the merman. Then he procrastinated the conversation with Erwin that he knew was coming by cleaning out the fish tanks and exhibits. And then he reorganized the filing cabinets. And then he made calls to arrange getting the fish and living corals out of the cracked tank in order to drain the water and replace the glass. And then he went out for lunch and nearly ran into Erwin at the burger joint down the street. He didn't want to talk to the blond because he knew what he would say.

He obviously wanted Levi to head the process of rehabilitating the Merman and become his head "trainer." He doubted that the merman would appreciate having a trainer in general, much less Levi. He wouldn't be able to avoid Erwin forever, as he had undoubtedly noticed Levi's avoidance, but Levi didn't see head of tail of Erwin for the rest of the day. The fact that the blonde had not sought him out made Levi slightly nervous, and when he left the Research Center at the end of the day he half expected Erwin to randomly pop up out of the sidewalk.

But he never did.

Levi went to bed that night feeling restless, trying to figure out how he was going to meet the unspoken challenge that Erwin had proposed. He didn't want to deal with any of this, but Erwin had backed him into a corner, and it was only then that Levi realized that he probably hadn't seen Erwin for a reason. If Erwin had wanted to speak to him he would have found a way, even if he had to wait in Levi's driveway for him to come home. He had done it before, and Levi wouldn't put it past him to do it again.

He was leaving the next step up to Levi, trusting him to make the right decision, and that was almost as nerve wracking as the fact that there was a live merman living in the rehabilitation pool. He would never admit it, but he really respected Erwin, and letting the man down would be worse than losing an arm.

When he came into work the next day, he still wasn't ready to approach the merman, so he left the job of feeding him to Hanji, which made her giddy with excitement. He swapped jobs with Oulo and Petra all day, now avoiding the merman rather than Erwin. Hanji had a meeting scheduled with Erwin, so he would wait until the scientist was out of the way to make a move.

But of course Hanji had to go missing.

She had never returned from her mission to feed the merman, and Levi was seriously concerned that she had been drowned. After fussing around with the pamphlets at the front counter and getting shooed of by Petra, he couldn't put it off any longer, so it was with great reluctance that he made his way to the outdoor facility. He was slightly surprised to see that Hanji was not outside with the merman.

He was even more surprised to find that the merman wasn't outside either.

Oh fuck, Hanji, what did you do?

The merman was gone and Hanji was nowhere in sight. His eyes landed on a fading water trail that led to the management facility. Levi followed it, already planning the ultimate chewing out speech for Hanji. He didn't know how the merman got out, but Hanji definitely had something to do with it.

He stopped in the doorway when he saw the merman attempting to break the glass on the front door. He was clearly struggling to hold up his torso while simultaneously trying to punch through the glass. He had a soaked rag thrown over his gills and there was a piece of metal sitting on the tile floor.

The merman hadn't noticed him yet, and Levi crouched down and silently padded forward. He needed to get that weapon away from the merman, and he prayed that the merman would be too distracted to sense his approach until he got ahold of the weapon.

Levi was right behind the merman, carefully reaching up to snatch the metal skewer away. He held his breath as he deftly pulled it away, slipping it into his pocket. The merman was oblivious, pounding his fist on the glass in frustration. He was clearly exhausted, breathing heavily as he allowed his body to sag to rest for a moment. He wasn't used to moving around outside of the water, and the energy he needed to escape had left him after all the strain of moving his body around on land.

Levi moved away from the merman and tried to assess the situation. He should call for help. Now that the merman's weapon was gone, it would be easy to surround him and corral him back into the pool. He was about to make a call into the radio at his side when the merman backed himself up, laying down to rest. The merman was still, save for his back raising up and down as his breathing settled. The merman couldn't see him from where he was, but Levi could see his face, and what he saw there made him feel guilty.

Those bright green eyes looked angry and full of fire, but there was something underneath them, a desperation that made Levi pause. He watched as the merman closed his eyes, his frustrated face softening as he seemed to make a decision.

When he opened his eyes there was a look of defeat in them that Levi felt was very out of place in those bright green oceans. But the fire was still there, burning just underneath the surface. Levi slipped into one of the offices, peeking through the blinds of the glass window to watch as the merman somehow managed to turn himself around and get back down the hallway, not noticing the missing skewer.

Levi left the office and followed behind as the merman dragged himself back to the edge of the pool and slipped back into the water. The merman reached his arm up a moment later to deposit the rag at the edge of the pool and never resurfaced after that.

Levi sighed and closed the door of the facility, locking it for good measure and making a mental note to clean up the mess the merman had made later.

He would come back to check on the merman later. For now he needed to find Hanji and give her that speech.