I SWEAR I...
(Warrior!Reiner x Reader)


A/N: So, I understand there may be some confusion regarding why I call Reiner a 'Warrior' here. Basically, So, I understand there may be some confusion regarding why I call Reiner a 'Warrior' here. Basically, SPOILER ALERT, an integral part of Reiner's character in the manga, is that he is revealed to be severely bipolar. One side of him is his honourable 'Soldier' side, the friendly, tough Reiner who fights alongside his friends to defeat the Titans. On the other hand, there's the 'Warrior', the Reiner who fights for the Titans, and doesn't hesitate to hurt or kill those who once stood by him.

I find this fascinating, even if it is rather tragic. Reiner switches from being truly evil, to truly heroic, and it's both saddening and intriguing. I kind of wanted to write about this part of his character, since I feel like it's sometimes overlooked in its severity. So I decided to write a short little fic which kind of explored this side of him, while also throwing in a little Reader action ;)

Anyway, enjoy!

Also, side note, Reiner is probably my biggest anime crush ever. I'll take any excuse to write about this blonde hunk XD


"I swear I won't tell anyone!"

Those eyes.
Steely. Gold and cold.

You desperately tried to seek some semblance of humanity still remaining in them.
But you found nothing.
Nothing but the insatiable desire to harm, to hurt, to kill...

Why didn't you just keep your mouth shut? Why didn't you just button up those plush little lips of yours and pretend like you knew nothing?

You knew why.
Because you were stubborn, and ferociously honest. You believed, firmly so, that a person's soul died the moment they stopped being true to themselves. If you ever chose to kowtow and give up your own morals and justified opinions...well...never mind the Titans, or Shadis, or any other party who tried to hurt you, to doubt you.

When you gave in...that would be the moment you truly lost.

Yet it seemed like you had lost even in honesty. Perhaps sometimes it really was a better idea to lie. To plead ignorance. To sit there with your hands squeezed between your knees to keep them from shaking, a happy little smile on your thinly pursed lips. To just keep quiet.

"Y...you're a Titan, aren't you?"

Why did you say it?
Why the fuck did you say it?

Idiot.

As you sat there on the bed, or more like cowered, his shadow engulfed you. The tall, blonde, muscled man was hovering over your form, which had scrambled back against the sheets in desperation. You wanted to run, but his taller, darker companion was blocking the door.

"[Y/N]..."
His voice rumbled like thunder, as he slowly lowered himself over your form, pressing his slightly rough hands against the bed around you. Unable to hold it back, you let out a small whimper of fear, as you watched him get closer. So close you could smell something faint on his jacket.

Blood.

That bitter, metallic scent, would have told you everything you needed to know, even if you hadn't seen it happen.

You had happened across him in the woods, when you had been split up by the Corporal into small, separate groups, while out on a scouting mission. Hunched over on his haunches in noticeable Titan form, with Bertholdt climbing up his back and to the nape of his neck, before cutting him out of it. You had watched your dear, tall friend, pull your other dear, muscled friend, from something which couldn't be called a 'friend' at all.

Of course, you had immediately darted off after the initial shock faded, and as you had whizzed between the foliage of the forest trees, your mind had ran endlessly through all your options.

Tell Levi?
Tell Erwin?
Tell someone? Or keep it to yourself?

You knew that if anyone else found out, then Reiner and Bertholdt would be marked for imminent death. Though this proved that they were a definite risk, you weren't so sure you could witness them being slaughtered without feeling a tremendous amount of guilt, and pain. Their lives were effectively in your hands, and no single decision had ever mattered more in your life.

Unable to summon the nerve to tell your superiors, you had instead chosen to try and reason with the two of them. After all, wasn't it better to hear them out first? Especially considering that Annie had been turned to crystal, so there would be no talking from her. Your two former friends could, hopefully, clear up the cloud of confusion around why the Titans did what they did.

Or so you had naively thought.

Reiner leaned further over you, making sure that all you could see above you was him. It would have almost been romantic to be caged between his arms and legs like this, had he not had a look on his face that said he wanted to murder you.

Through white, gritted teeth, he spoke lowly.
"...How do you know that?"

You nearly choked when he addressed you. How could someone who had been your companion for so long suddenly turn like this? You shot a desperate glance to Bertholdt, but his eyes were averted, and he looked a little pained by the proceedings. Looking back up at the blonde boy over you, you struggled to answer.
"H...How do I know? W...well I...I just...I saw you. I...saw you in the woods..."

Reiner blinked, then leaned back a little like he was realizing his err. Obviously, he hadn't been expecting someone to happen across him and Bertholdt back then...
Something quickly changed in his eyes, as he shifted off you and let you breathe again, his body pacing thoughtfully around the room.

He raised his hand to his mouth and nipped at his nails.
"...You told me nobody was watching, Bert."
"-!" The boy by the door flinched, and looked at him with hooded eyes. "I..."

"No EXCUSES!" Reiner suddenly roared, spinning round and facing him with furious eyes. You flinched violently while he shouted:
"-You SWORE!"

Bertholdt looked a little less alarmed than you, but still shaken. You didn't want him to get hurt just because you'd let your mouth run, so you swiftly spoke up again.
"R-Reiner, I swear I won't tell anyone! Please!"

Yet again, he changed. His anger faded, and he turned to you with a much less volatile stance. Slowly approaching your now sitting form, he crouched by the bed so he could look you straight in the eyes.
"[Y/N]...you have to promise me. Nobody can know about this..."

Swallowing thickly, you gave him a tender nod.
"I...I promise...

You swore twice. You promised.

But it was hard. All throughout training, you couldn't stop thinking about the way that things had played out in Bertholdt's room. You had gone in there with high hopes, and come out chilled to the core.

Reiner wasn't okay. You couldn't quite put your finger on it, but for many moments there he had seemed like a completely different person. It seemed that he was losing grip of a part of himself...the part you all knew, the part you all trusted. Maybe that explained why he had done those things as a Titan.

You remembered it...seeing that massive form charging down the wall and running through the city with thundering footsteps that cracked open the very cobbles beneath your feet. A gargantuan monster...

It was the same question you had asked when you had found out the truth about Annie. How could that be the same person? At least in Eren's case, you had all seen it happen right before your very eyes. But Reiner...Annie...Bertholdt...it just didn't fit together in your mind, even though the evidence was so blatant right before you.

You paused for just a moment.
The blood...where had that come from anyway?

Mikasa just about took your head off with a well-aimed kick, but stopped herself just in time when she noticed you had zoned out. Quickly pulling back, she breathed a sigh of relief and frowned, watching you.
"[Y/N], you need to focus. That was close."
Blinking back to reality, you looked over at her, and forced a wavering smile.

"Sorry."

In that moment, you had wanted to tell her everything. But you kept it to yourself. You were still seeking answers...

Reiner had forced you to keep your mouth shut about this, made you keep those promises you had made on the spot like that. Not that he had laid a hand on you. No, you were scared into submission simply because you were afraid of provoking that side of him again. Seeing it emerge like a feral beast...

You feared for Bertholdt's sake too.

The two of you sat on his bed just like before, waiting for Reiner to arrive. It was late, and candles were flickering on the window-sill. You watched the melting wax drip down the side and form hard pools by the bottom. You eyed the red flame, your gaze drawn into it, as if it could make you vanish.

"So uh...how did training go today?"
Bertholdt, making small talk as usual. He often did this with you, mostly because you made him shy.
Looking over at him, you let out a soft sigh and shrugged. "OK, I guess. Though I've been pretty distracted recently."

He smiled just a little, but it looked as melancholy as usual.
"That's...understandable. It must have been a lot for you to take in."

Pursing your lips, you thought for a moment, before making your decision, and shifting a little closer, which made him slightly flush. You lowered your voice.
"Bertholdt...can you be honest with me?"

Hesitating, he avoided looking you right in the eyes.
"I...I don't know, that depends."
Letting out a small sigh, you looked down at the sheets, gripped them, then looked back up at him again.
"What's wrong with Reiner?"

His emerald eyes widened slightly, then he bit his lip, but hid the action behind his knuckle.

"Please Bertholdt, you have to tell me. I'm trying to understand."

You begged him, and you hoped he would understand. Couldn't he? You were looking past all he and Reiner had done, the invasion of Shiganshina, the affiliation with Annie (which they had confessed to, at least), their constant lies and their betrayal. They were relying on a mere few promises to keep you from ratting them out, but you hadn't come close to betraying them yet.
It was a small ask.

And thankfully, Bertholdt seemed to understand that. Clasping his hands in his lap, he sighed softly.
"Reiner is...fine, most of the time. I mean...he's been getting worse though. He uh...he kind of has...two sides to himself."
You listened with admitted interest. So, you had been right on the money.

Bertholdt continued, and told you all that he knew. Reiner seemed to be split into two people, in the same body. On the one hand, there was the Reiner you all knew well. The noble Soldier. The man who would risk life and limb for the cause of protecting humanity.

The polar opposite- his Warrior side...that was the side that was with the Titans. The side you had seen in the bedroom that time, when he had pushed you down on this very bed and spoke so threateningly. When he had snapped at his best friend in the world, not even caring how scared it made him.

Suddenly, it all seemed to make a lot more sense...

Now you sat on that same bed, still. Yet instead of Bertholdt there, it was the man of interest himself- Reiner. Bertholdt had left you two to talk, after Reiner had requested it of him. For a moment, you had worried he might have overheard you talking about him or something, but thankfully he seemed calm.

You watched his face, lit in the orange glow of candle-light, the dim hues of the room giving his blonde hair a dirty tinge.
He looked torn. Like he was struggling between two extremes, and now you knew that was literally the case.

You feared him. But you also pitied him.
In a way, you too, were torn. You were almost kindred spirits.

Besides one simple fact...

"...Reiner...I can keep this secret for you...but-"
His eyes slowly swivelled over to you, and you gulped, but refused to shake. Besides, he just looked sorrowful. Though in a way, that was worse.

"-I...can't forgive you for what you've done..."

His eyes suddenly widened, and for a moment, you swore you saw tears pricking them. It was as if...your opinion was what he truly cared about. But why? Did he really think he could somehow still justify what he had done? Especially in your eyes?

Still justify killing all those innocent people? Snuffing out those innocent lives with just a single step?
Could he excuse all his lies? The way he had betrayed his friends? Betrayed you?

Apparently he did. His delusional, glazed gaze focussed on you, his hands going to your arms and gripping them tight. Yet he gently leaned forth and pressed his forehead to your chest, huffing out a heavy sigh. All you could hear was his laboured breathing, and all he could hear was your frantic heartbeat.

He spoke so quietly, you almost didn't hear him.

"I swear I...didn't mean to."