(Atsumu isn't genuine in the beginning about liking you. He only becomes genuine after the first couple of times of sex and not being able to understand why you won't become wrapped around his finger like the others).
He begins to feel desperate about what he can do to turn your attention to him and make you want him more than just a casual sex relationship because it bothers him that you're treating him like he's this disposable toy, and he wants to change that by letting you in on some of his private life and tries to go out his way to spend his free time with you somehow. Then he gets to know about your private life and actually becomes interested in you.
He says that he's truly taken a liking to you and he wants to make you his woman. He says that he can offer you're the finest things, take you out to the fanciest places, but in response to that, you say nothing and laugh.
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It takes him a while to figure out that you genuinely could care less about him or status. He's confused by the turnout, so he stops to ask you one time what this is but he catches himself before he finishes. However, you smirk because you already caught on to the question.
"Miya-san, were you trying to ask what this was?" He glared on silently as the red faded into his face. "Someone like you, asking little ol' me that question...I'm speechless."
"It's not-"
"We're fuck buddies," you barely tilted your head. "Duh. Isn't it obvious at this point?" You pointed down to his crotch. "You know how to use that thing between your legs pretty damn well, so I'm using it when I feel like it. And it's vice versa, ain't it?"
"Of course it is..."
"Unless...Could it be that you're-" Your toothy grin stretched wider.
"Hey, aren't you giving yourself a bit too much credit? I was just making sure you weren't getting the wrong idea yourself. I've had too many women in my past asking me the same question, so I wanted to make it clear here and now."
"Then how about we make it official?"
"Official?" His forehead scrunched together. "You mean like as a couple? But you-"
"Oh gosh, no. Officially fuck buddies. I mean it took us up until this point to address it, so why the hell not just say it now."
"Fine. We're fuck buddies then."
"Just try not to fall for me, okay?" You glance just barely over your shoulder. "Anything more than this isn't my thing."
It's then that he understands he's the one who's been dancing in the palm of your hands. It irks him, but he hands it to you.
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Atsumu agrees to it but despite this, he goes on to send gifts like lingerie wrapped in a box to your workplace. He excuses it the first two times saying he personally wants to see you wear them in bed. Or he's just doing it because he wants to and you don't have to think of it as anything.
But when you tell him more about yourself and what you like to do in your spare time, he starts to get more attached. And even having genuine cute moments together like teaching him how to crotchet and him failing. Your laugh makes him blush and his heart speeds up.
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To him, it seemed like you were really taking a liking to him But at this point, you still haven't fallen for him. You're only warming up to him bit by bit. But after a while of having sex, Atsumu notices your self-harm scars after you come out of the shower in the middle of foreplay, where he's kissing the mole on your wrist. He hadn't noticed them before; he wonders why he never noticed them before, but while kisses you all over, he noticed the very faint scars. He questions what's wrong, but he shakes his head and continues on. He wants to ask, but he doesn't want to ruin the mood, so he pushes it to the side.
Oikawa might come in a conversation between you and Atsumu, and it gradually irritates him. He understands that he's your boss, but he doesn't like the guy because he feels as if he might be into you, since he caught him looking at you strangely. With those bedroom eyes early ahead. At this point, Atsumu is gradually starting to grow legit feelings for you. In response to this assumption, he begins to send orders from restaurants or have Goda drop off gifts for you at G.K headquarters, like lunch or pastries. Sometimes he will call beforehand and ask if you've eaten breakfast, he'll send out brunch for you. With this, your coworkers as well as Oikawa notices this and starts to think you've got a boyfriend. You deny it in a conversation with Takagi and Asahi. But Oikawa passes by in the conversation and glances at you, which forces you to say later on in his office that you don't have a boyfriend of the sort. He asks why you felt the need to tell him that, all while looking glum, but you tell him you didn't want him of all people to get the wrong idea. Oikawa's heart speeds up a bit of your consideration for his feelings and what he genuinely believes to be your honesty. "I only have eyes for you, Tooru. You know that, don't you?"
This is not the time where he asks you to be his girlfriend.
Even though you tell Atsumu you appreciate the food, you tell him he needs to stop because people at your job are getting suspicious of you. He hears you but doesn't listen. He takes a break from sending them to you, but after his feelings develop a bit more and he realizes he doesn't want to back down, he shows up in person and drops them off at the front desk for you to have later. He also states who it's for, but tells the front desk man to keep it a secret.
You tell him again to stop, but he says he doesn't want to. Within the next couple of days, he sees you and Oikawa coming in or going out, and that's when he gets the confrontation.
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Atsumu will not know that you let Oikawa touch you before this. It's when he continues to keep sending gifts, that Oikawa passes by one time and sees them all piled up at the front desk, which bothers him. He asks who they're for and the front desk woman says that it's for you. Oikawa questions you later, but you tell him that it's just someone trying to court you, but even though you've turned them down, they still send the gifts. Oikawa then says that the next time he sees them send it, he'll trash them. He then says that he can get you even more than that. This bothers you greatly, but your bite your tongue and let him run his mouth. The next time the gifts come, Atsumu is bringing them himself. He tries to ask for you, but the front desk woman tells him that both you and Oikawa are out for lunch, but should be coming back at any moment. He smiles at her and says that he doesn't mind waiting.
Just then you both come back and that's when Oikawa confronts Atsumu about being the one to sending you gifts. He tells him he's being a little over-friendly, but Atsumu says it's on purpose. Oikawa then sends you to make him some coffee while you tell Atsumu to come with you to a separate room. Oikawa goes on to lie and tells him that you told him that you hated the gifts and threw them all. He then goes on to proclaim that you are his woman.
"Listen to me and listen to me good, asshole. (Y/n) isn't interested."
Oikawa goes on to tell Atsumu that you have someone else and much better in your sights, which he implies with a smug look is him. This makes Atsumu furious, and he's annoyed to think that he was played by you. He feels used, humiliated, and upset, and his heart truly breaks upon hearing this. Atsumu trashes the bouquet on the way outside and leaves with shame on his shoulders.
When you return with Oikawa's coffee, he's smiling happily. You act as if you nothing much to do with him after getting the deal. You told Oikawa that Atsumu seemed to have taken a liking to you as an admirer, but even though you refused him, he still chose to pursue you. Complete lie.
You ask him what happened to Atsumu, so he happily grins and tells you that he wouldn't be coming back to bother you any further. You ask him what he means by that, and he tells you everything that he told him. You're infuriated so much so, that when he tries to touch you at over hours, you completely deny him and tell him you're going home. He doesn't understand why, but he keeps his distance.
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When you get home, you find Atsumu's card and finds the directions to his company. You take part of your lunch break time to go to a storage room and CALL him, but when he answers his tone is cold. He demands to know what you're doing here, even going as far as using your last name with honorifics to distance to emphasize how angry he is. But you respond by telling him that whatever he heard wasn't true.
"You really expect me to believe that? That you're not his secret mistress" —- Ari told Atsumu that she and Oikawa were engaged.
You tell him to give you a bit more credit than that. At this point, he's gotten jealous over you because he's starting to take an actual liking to you. And when he tries to tell himself that you're just another woman who he just happens to be his fuck buddy, he hates himself for falling for you when he shouldn't have. He has to admit that he doesn't like anybody touching you or flirting with you because he likes you. But he doesn't want to admit it to you. You try to pry it out of him regardless, telling him that he's the one who wanted to be sex friends in the first place. And it doesn't matter
"I don't like sharing my belongings to,(Y/n)."
"And you think that I belong to you, Miya-san?" His silence makes it hard to suppress your laughter. "I met a man like you once. I guess you both have something in common." He raised a brow. "You're both comedians. Let's agree to call you for what you are, Miya-san. Greedy."
You argue for him to stop making up crap and ask him if he was really going to believe the same man whom he hated.
"Then you tell me what the truth is, (y/n) And just what did you come here for? Explain to me why you rushed all the way here."
"I came to clear up the things that my foolish boss fed to you. I don't belong to that man, nor will I ever."
"You're doing a sucky job of defending yourself. Unlike that asshat. He sounded super convincing about what's going on between you two. And you know what pisses me off, I don't even have a reason to doubt him."
You have nothing to say at first, which forces you to admit that you do have a bit of a promiscuous relationship going on, but it shouldn't matter since he's enjoying himself as well. This irks him further.
"You're right, Haruhi. I'm a very greedy man. Sharing really isn't my thing."
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Watching you walk out of his office, Atsumu felt torn up. He was still upset over Oikawa lying to him, and then to hear you were intimate with another man, and now he had to admit that doing this sex friend thing wasn't going to be enough for him. And now he was getting upset over the fact that Oikawa was the prime suspect to you doing self-harm.
But you tell him that if he needs to send you something, it's best you do it through the front desk of your complex.
--Shortly after this, you're running late after a night of fooling around with Atsumu and he offers to drop you off at work. (ON THAT NIGHT HE WAS ROUGH AND EXTRA DOMINATE TO SHOW YOU THAT HE WASN'T GOING TO LOSE TO OIKAWA, TELLING YOU WHATEVER HE WAS GIVING YOU, CAN'T COMPARE TO WHAT HE'S GIVING YOU RIGHT NOW. THIS IS THE FIRST TIME HE'S FORCES YOU TO CALL HIS GIVEN NAME.
"mi-miya-san..."--"Wrong..."--You huffed as he grabs your breasts. "Atsumu!"--"That a good girl," he breathed.)
But because you don't want anyone to see, you tell him dropping you off a block away would be fine. He's reluctant, but does so anyway and heads off to work. During the car ride, you ask him if he can really pull it off?
"Watch and see."
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Oikawa takes you out to dinner when he asks you to leave early with him, saying he would give you a lift home. After this, he ends up with either of you getting intimate in his car. Feeling slightly guilty afterward, he decides to buy something nice for Ari, yet ends up buying you something as well (a beautiful pair of heels After finding out that you like wearing heels. When he leaves during the day to take a trip to the mall to buy a couple of items for Ari. He brings you along to be able to help him pick certain outfits out before meeting her for the night.
"Oh these? They were a gift from a certain someone I used to know back from high school."
"That guys must have a crush on you."
"Well, who knows for sure."
"Would you return his feelings and date him? For as long as I've known you, I don't think you've ever date someone."
"We'll see," you plastered a smile.
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One of the Inarizaki boys will be keeping and eyes on Ari and her plans. Once wind gets out that she's going on a weekend getaway with 2 friends, Osamu sends one to approach the girls on their last night before going home, even though she'll refuse because she's engaged. But that person will then turn around and order her drinks in order to celebrate her engagement. She awkwardly thanks him and goes back to being with her girlfriends. Throughout the night, of her drinking her friends, who are already tipsy, leave her by herself and go off with strangers, who're a part of Osamu's crew. In reality though, the girls are being le to where two more members 'assault' the boys, blindfold, and finally kidnapped the girls.
While the girl are among themselves, Ari's two friends sow a seed into Ari's head by asking if Oikawa's really able to control his urges, since she told them that he always holds himself back for her sake and is respectfully waiting for their marriage until to take things further. She questions them on what they mean, and one of them ask:
"Doesn't your fiance have a woman for a secretary
"Ehh? There's no way!" She waved a dismissive hand at the claim. "Tooru-chan is the sweetest guy I know. He always shows me so much love. And (f/n)-chan. Well...she can be hard to read a little, but she did tell me once that she's not looking for any kind of relationship. She's kind of really cool, in my opinion. I don't really have a reason to suspect them."
"Maybe they're just that good at hiding it."
No..." her voice shriveled up.
Okay, okay, let's talk about something else. We didn't come here to upset the birthday girl."
"That's true. Sorry, Ari. We just want you to be careful."
"I know...thanks."
Atsumu also hires two guys to tail and coax Ari and catch her in the act of cheating on him. Which was set up by him so it would look like she lied about going on the weekend trip with her friend and made it look as if she had gone to meet him and sleep with him? When the photos are taken, Osamu's face is blocked/blurred so they can't see who it is.
When neither of the girls picks up their phone, she gets up and walks out. She a bit more on the drunk side. She tries to get a hold offer manager to come pick her up, but her vision blurs. She tries to leave and get some air by walking for a little bit, but end up being tailed by Sakusa for a couple blocks. Eventually she winds up strayed away from the bar and lost. When she turns a corner, she will bump into Osamu. She apologizes and tries to step away to escape, but he catches her hand and asks her what's wrong. She tells him that she's being followed by someone, and he's coming around the corner soon. He notices that your tipsy. He says it's not good for her to be out by herself in this condition. He then excuses himself, and puts his hand around her shoulders, making her blush, and telling her to follow him to help deter him. She agrees and they go around until they make a stop at a restaurant, and he asks her if he wants to go in with her, she's hesitant, but is reassured when he says he'll show her the way to the train station.
He doesn't offer her a drink, but she order one anyway because she's a little upset and worried about her friends going off on their own without her. She vents and he lets her. They talk for a while, and she notices that he's looking at her awfully weird. Like with bedroom eyes. But she blushes and says nothing. When he finally walks you back her little cabin or hotel room, she has a bit of guilt about asking, but still goes through with asking if he wanted to come in for a bit to wait with her until her friends got back. He smiles and goes in, and they watch a movie together, in the middle of the movie, Osamu puts his hand around her side of the couch and she blushes. She tries to get a snack, but Osamu pulls her back, tumbling into her lap.
"Normally, I'm a gentleman, but there's something about you that can't make me wait."
"Um...I'm sorry. I'm flattered but I already have someone." She flashes her hand, but he just holds her hand and slips it off and chucks it over the couch. She yells at him for doing that, but he grabs her when she tries to go get it. This time, he smashes his lips into her and forces a tongue kiss down her throat. She tries to fight back, but goes weak to it, especially when he touches her between her legs. That's when she gets drowned by the pleasure and does it with it him.