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He had invited her over for a very simple reason. To have his own needs satisfied and all desires met, he knew she could do it from the previous times they'd spent hours locked away together in his room.
Right now, though, while she was sitting on his bed scrolling on her phone with his metal music blasting surely loud enough to annoy Armin, he saw something else. He could only see Mikasa in her face.
Sure her hair and lipstick colours were slightly different but they still matched the style Mikasa commonly wore hers in. He thought she seemed more smiley though, bobbing her head along to the beat of the tune in the background before turning her head up to meet his eyes.
"You coming to bed anytime soon?" That wide grin was back spread across her face once more as his green eyes burned into her own, she wouldn't back down.
Eren felt slightly frozen in place and for the first time since he'd seen her he questioned what he truly wanted from these encounters. Right now he wanted to fuck but he was craving something more too. Some part of him desired support in this moment that he knew no one but Armin could give him. Poor guy was probably trying to will the music blaring to block out the noises he knew would inevitably rise in volume.
"Do you...?" He paused not knowing what he wished to say or ask for a second. The woman looked puzzled internally attempting to decode his question. "Do you want to have a threesome?"
Fuck.
He knew many people called him impulsive and the bizarre thoughts he spouted outrageous but this was a new level of word vomiting. Her eyes were saying something he couldn't quite understand but her mouth hanging wide said a huge "NO" directly to his face. This was beyond embarrassing and to think he was still seriously hoping for her to agree was-
"Who with?" Was he dreaming? "I'll do it only if I like the guy yeah?"
Armin was going to kill him. "My roommate... Armin."
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The blond roommate had been sitting quietly on his own bed slowly sorting through pictures on his phone before he planned to tidy up his room. It was far from a mess, he just didn't like to let anything pile up when he had a break from schoolwork. He vaguely recognised one of the songs bleeding through the walls as he tried to think.
One single harsh knock hit his door before it flung inwards to reveal Eren's form leaning on the frame. The brunet's lips were pressed together as if he was desperately trying to keep a secret locked inside. This set him on edge immediately, Eren had done something, and he knew he wasn't going to like it.
"So there's this girl..."
Armin blinked and inhaled deeply, trying to conceal the slight furrowing of his brow "Right?" He urged his friend to continue.
"I may have made..." The brunet had almost admitted to being wrong, however, he was still incapable of apologising, "I need you to do something for me."
"Can I know what it is before I agree?" His brows crinkled further.
Unprompted Eren moved towards his dorm mate's bed proceeding to grab his hand and drag him to meet the girl, "You'll work it out."
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"You prick." The blond mumbled behind himself.
She looked up from her phone as the pair of boys walked in, she set it beside her giving Armin a once over with her eyes.
Standing up off the bed she stepped forward to meet the two and swiftly busied herself by placing both hands on either side of the blond's face. Flicking her eyes to catch Eren's expression before initiating a kiss.
Armin knew her only from the times she came over to screw Eren, he heard the majority of it and, sometimes if he couldn't help himself or he was especially stirred up he'd use their noises to get himself off. He was sure his friend knew it by now if not from accidentally hearing him through their paper-thin walls, then he definitely gave himself away with how he would refuse to make eye contact for the rest of the day and carry a guilty expression on his face.
It was perverted. And Armin was willing to bet that was the number one reason why Eren had been so sure he would agree to something like this in the spur of the moment, no questions asked.
She pulled away meeting him with eye contact as they both caught their breath before she turned to Eren and dug her index finger into the front of his sweatpants, pulling him with her back towards his bed.
Had Armin seriously just signed himself up to be a cuck?