Four simple words were all it took, "Do you trust me?"

It wasn't a mystery that Armin looked up to Erwin, or that Erwin himself held a certain level of respect for the younger man. There was a level of trust between those two that most people hadn't even found themselves. The connection they held was obvious to everyone, though to them it just seemed innocent.

What they didn't know though, was what happened behind doors. And it was best to keep that as secret as possible.

Erwin wasn't one to take his soldiers to bed with him. He liked to keep things strictly professional. When Armin came along however he found himself pushing those morals away, and within a month he had the smaller boy underneath him moaning and writhing and begging for him to go faster. Armin was rather unexperienced. His hands would fumble and shake and his cheeks would be dusted with a blush. Erwin found it captivating. Adorable even. But the sex so far had been rather… weak. Oh, it was good alright, but Erwin found himself wanting to do far much more to the boy then simply pulling him underneath his large frame. He knew Armin didn't know a whole lot about what all sex could be, and he decided he wanted to teach him.

Everything.

Those four words were all it took to have Armin kneeling on the floor, arms bound behind his back, and a blindfold over his eyes.

"Is this okay?" Erwin asked softly. He ran his hands through the boy's blonde hair.

Armin nodded, unable to keep himself from biting his lip nervously. He'd never even heard of sex happening this way. He had to admit that it was hot. The heat pooling in his gut was a clear sign of that. His cock stood up and he was near begging to be touched.

And then there was a knock on the door.

"Give me a second!" Erwin called out. He put his hands underneath Armin's shoulders and lifted him up, cradling his thin frame and easily carrying him over to his desk. Armin bit back a squeak of surprise at the sudden movement and wiggled around a little in the bigger man's grip. Erwin's hold on him only tightened. He put him underneath his desk, safely hidden from the view of the door, and crouched down to whisper in his ear, "Don't make a sound, let me take care of this really quick." And he pulled the ball gag from a drawer and fastened it to Armin's head. Just to make sure. Armin tongued at the ball in his mouth curiously, squirming around in the tight space trying to find some sort of comfortable position.

Erwin opened the door to a rather suspicious Levi, "Yes?"

The smaller man's eyes narrowed, "You have another fuck toy in here don't you."

Erwin smirked, folding his arms and leaning against the doorway, "What makes you think that?"

"Your face. I didn't even know there was a whore house around here."

"There's not."

"Then where-."

"What did you need Levi?"

Levi glared up at him annoyed at being interrupted, "You have paperwork to fill out about the last experiment Hanji did with Eren. Here." And he shoved the papers into his superior's hands and left.

Erwin watched him leave with a sigh before he turned around and closed the door behind him. He placed the papers in a drawer before crouching down to pear at Armin. The sight was delicious. Already the rope around his arms was chafing the skin red and the gag was slick with saliva. He hadn't gone soft, and that pleased him. Eventually he spoke up, "Sorry about that pet."

He heard Armin moan around the gag and smiled, "Do you want to continue?"

There was a small noise of agreement. Erwin reached underneath the desk and pulled the blond boy out, setting him on top of the desk.

"You look beautiful."

Armin tongued at the ball gag in his mouth and whimpered softly.

"Do you want me to touch you?"

A small, embarrassed nod.

Erwin leaned in closer, catching the boy's earlobe between his teeth, "Do you want me to fuck you?"

Armin moaned and squirmed, nodding again.

"There's so much I'm going to teach you," he whispered, "so many things you've yet to experience and I'm going to be the one to test them all with you. This is just the beginning, and if you like it, we'll do this more often." His fingers found his hips and he rubbed them gently. "I'm going to break whatever innocence you have left in you."

The boy moaned breathlessly, arching his back against him. He pressed his naked body against him, far too turned on to care that he was the only one without clothing. Erwin chuckled and pushed him away, laying him flat on the desk with only his legs dangling off. Armin squirmed and moaned desperate to get any kind of relief.

"You're cute," His commander commented. He ran his hands over his chest, pausing to tweak at his nipples making him shudder. "Turn over."

And he did.

The first smack against his arse caught him off guard, making the smaller boy shriek into the gag in his mouth surprised. Erwin ran his hand over the reddening skin and smiled softly, "Is this okay?"

Slightly unsure, Armin nodded. He trusted him after all.

He was more ready when his hand came down across his other ass cheek. He even managed to bite back a small scream. The hands on his skin soothed him and the tenseness in his body slowly left him as he relaxed against the desk. Another smack, another small shriek, and he found himself rutting into the desk desperate to feel any sort of relief.

"Stop that Armin," hands at his waist stilled him, "If you can't wait then I'll just leave you here."

Armin dropped his head against the desk and nodded. He braced his legs, barely in time for the next blow against his ass. He keened then and tongued the gag in his mouth desperately. His ass stung but in a way that was gloriously good. He wanted him to keep smacking him. He didn't want him to stop until he was crying. He didn't even know that this sort of thing could turn him on so much. All he knew right now was that he wanted more. He wanted to talk. He wanted to tell Erwin to stop teasing him and to just get on with it. He felt himself grow red at just the thought of begging him to take him.

He forced himself to relax again expecting Erwin to continue to spank him. Instead though, a slicked finger found its way to his entrance and plunged inside. It burned with how fast his finger had entered him. But it burned good. Armin shrieked and bucked his hips and shook his head so his hair could hide his face because even if he couldn't see anything he could feel Erwin's eyes burning into him and it was embarrassing.

A hand entangled itself into his hair and pulled his head back sharply, making him gasp in surprise. Erwin's lips ghosted over his neck and up to his ear and that voice, oh god that voice, was whispering to him and making him feel hot, "Don't hide your face from me love, I want to see everything."

And his finger started moving. One finger turned to two and then to three. Moans turned to cries and then shrieks because he was fucking him with his fingers so fast and he kept teasing and brushing against that bundle of nerves inside of him and Armin just couldn't keep himself quiet. He knew people would be able to hear him if they happened to walk past the room, but at that moment that was the least of his worries.

And then the buckle keeping the ball gag around his head was undone and his mouth was free and he was begging.

"Erwin please, please hurry."

"What do you want?"

"I- I don't-." He couldn't bring himself to say it. He knew it was what Erwin wanted to hear. But it sounded too vulgar and he just couldn't form the words with his mouth.

"I can keep at this for a while Armin. I'll wait as long as I need to for you to tell me what you want."

"I want…," Armin shrieked when those fingers curled inside him, "I-, oh god I… ah! Please, f-fuck me."

And then those fingers were gone and Erwin was entering him, inch by agonizingly hot inch, slowly and steadily and Armin was screaming. He felt so good, so hot, so full, and he needed more. He needed him. He needed Erwin to fill him up completely and use him. He felt fingers caressing the sides of his mouth where the skin was left red from the gag.

"Do I feel good Armin?" was Erwin really just as breathless as he was? Or was he imagining it?

All Armin could manage was a whispered and drawn out, "Yes."

Then the older man had him pinned against the desk with his hand in his hair and he was moving, so hard and so fast and so good. Moans and screams and cries fell from Armin's mouth and he couldn't stop them. He couldn't mute them and he couldn't even put his hand over his own lips to smother them because his arms were still tied behind his back. Erwin's hand was tangled in his hair and pulling slightly and he had a bruising grip on his hip keeping him steady and still. He couldn't move back into those thrusts. He couldn't hold on to anything. He was helpless and blind and it was hot and he couldn't take it much longer. Erwin was fucking him so hard it almost hurt and he needed him to do it harder.

Right when he thought he was about to cum Erwin's hand wrapped around his cock, circling the base and squeezing tightly. He shrieked and bucked his hips, not quite able to reach his peak and almost hating Erwin for denying him. He kicked his foot frustrated and screamed out his name.

"Be good, Armin."

And with one rough thrust Erwin was draping himself over the smaller boy and filling him completely. Armin wanted to cry. He was still so painfully hard and hot and now he was dripping and it was all too much.

"Please," he shouted, "Please, please, please, please, please!"

Erwin pulled out of him and flipped him on his back, pulling the blind fold from his face and kissing him hard and fisting his cock. Armin moaned desperately into his mouth. He thrust his hips forward and biting almost boldly at his lips because his touches were so light and teasing and they weren't doing anything for him. And then those lips moved from his mouth to his groin and he screamed when that familiar heat closed around him. His tongue was doing things Erwin knew would drive the boy over the edge and god did it work. Armin shook and screamed and jerked his hips and even when he started coming down from that high he couldn't stop trembling because god it just felt so good. And then Erwin was right there pulling him into his arms and untying him. He couldn't even feel his fingertips or his legs. All Armin could manage was to slump against the bigger man utterly exhausted. Tired. He was so tired. Those skilled hands were moving over his shoulders and back and arms and kneading the muscles and the aches away and he needed to sleep.

"You okay Armin?"

He could barely manage a small confirming noise.

There was a deep chuckle in his ear and that hot, hot voice was whispering to him once again, "Go to sleep. I'll be there when you wake up." And Armin couldn't hold on to the small sliver of consciousness any longer and closed his eyes.

I plan on making this whole thing like a "Erwin breaks Armin's innocence" thing so I'm taking requests get as dirty as you want. The dirtier the better ya?