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Mako is a terrible brother. He knows he is.
He tried. He really, really tried to be the best brother he could be to Bolin after losing their parents. From protecting him from the scum of Republic City, to earning money from the Triple Threat Triad by running numbers for them so they won’t starve, to even saving his life a few times over the years, he was always there for his brother.
Of course, he wasn’t perfect. No-one is. He has done some stuff he isn’t particularly proud of which ended up hurting his younger sibling, but they always mended up and hugged it out at the end of the day. They were still brothers who always looked out for each other.
But not this time. This time, he has damaged their relationship beyond repair and Bolin doesn’t even know it. Neither does everyone else in their found-family.
All except one. Opal, his brother’s wife. His sister-in-law.
His sister-in-law who he’s sleeping with.
His sister-in-law who he’s currently fucking against the wall, right now.
“Mako…” She whispers into his ear, dragging her nails down his muscular back which causes him to groan in pain. He knows they will leave marks but he doesn’t care. Instead, he delights in the fact that traces of their time together will remain long after they’re done.
His arousal now amplified, he thrusts deeper and faster into the airbender with no hint of slowing down. She moans loudly and it makes him feel so fucking alive. He nibbles at her ear and growls into it. “You like that, don’t you?”
“Yes, yes!” Opal grunts and she keeps repeating that word over and over again like a prayer.
Not even fifteen minutes have passed since the Air Nomad arrived at the firebender’s apartment and they’ve already reached their climax. The very second Opal stepped into his home and the door was shut he pinned her to the wall and kissed her like he has been starving for weeks. In a way, he has, which is damning.
They’ve been having this affair for the past six months. Six months of secret glances, brushing of hands, kisses in corridors, and passionate sex in the darkest of nights all the while the world has no idea.
He sometimes thinks about the night that it happened. The night when they first kissed.
He remembers all too well.
Mako stands stiff and frozen as a statue as he gazes out into the mesmerising lights of Republic City. Even after all these years the metropolis that never sleeps always manages to leave him breathless with its beauty. He can faintly hear the party behind him on Air Temple Island, hear the cheers and screams of joy as they express their congratulations for the two women of the night.
If only he felt the same.
Taking a large sip of the red wine that was offered at the party, Mako continues gazing at the city he has spent so much time in protecting and realising where in the spirits did his life go wrong. Here he is, a twenty-six year old man, drinking his sorrows away as he tries not to burst into tears at the fact that the woman he loves is now married to someone else.
He should have seen this coming. Korra and Asami have been dating for four years now and happily so. He should have been prepared for this a long time ago.
And he was to an extent…but it doesn’t make it any easier.
Mako can still remember being stabbed in the heart when he saw Korra and Asami kiss all those years ago. He felt like a complete idiot for hoping even for a second that he would get back together with Korra. He felt like a massive joke that he wasn’t part of.
When he told her that he would always love her when they broke up, he meant it. He really did. No-one can ever replace the woman who holds his heart and he’s ashamed to admit that now. On the night of Varrick and Zhu Li’s wedding, he was planning on confessing to her there and then, tell her that he still loves her and he always will until he dies. It was on the tip of his tongue, ready to be spoken.
But he couldn’t do it. Instead, he simply told her he would always have her back. He was being completely honest when he said those words at the time and he stayed true to them now but…the bitterness in his chest remained long after he said them to Korra, angry at himself for being such a coward. In hindsight, it was best that he was a chicken. He would have only humiliated himself.
But after that kiss, Mako felt like he was a lonely spirit looking through the window as Korra and Asami loved each other. He was truly, genuinely happy for them. He was definitely not the best boyfriend back then and wants nothing more than his friends being happy…even if he wasn’t himself.
When Korra showed her betrothal necklace that Asami made for her, grinning brightly in a way he had never seen before when they were together, he knew it was all over. That tiny, tiny spark of hope flickered out of existence. Despite being a firebender, he never felt so cold.
Still, he didn’t let the pain ruin Korra’s best night. He put on a smile, one that was half genuine and half a mask to hide the pain, and gave them his congratulations. When she asked him in private if he wanted to be her best man, he simultaneously felt so, so honoured and so, so defeated. It was like the universe was mocking him, pointing and laughing at him for being so close to the woman he loves but still out of reach.
Bolin, bless his heart, gave him concerned looks and often asked when they were alone if he was okay. Mako wasn’t really surprised that his little brother knew of the love he still had for her, he was able to read him like a book most of the time. He always shrugged it off, gave him a smile, and told him he was just fine.
But now? Now, he’s alone and he doesn’t need to hide his feelings from everyone at this moment so he wallows in his sadness as he continues to drink from his glass.
“There you are.”
He turns to the direction of the voice and sees Opal walking towards him. Recently made an airbending master only a year ago, the young woman has the signature blue arrow tattoos all over her body but in her current attire of her nomad robes and cape the only sign of her mastery is on her forehead and the front of her hands. Her hair has grown back to its original length but she once made an offhand comment that she’s thinking about allowing it to grow slightly longer.
When she finally reaches him, the airbender analyses his face with her olive green eyes full of concern. “What are you doing here?”
Mako turns back towards the view of Republic City and shrugs. “Just needed some time alone. Are people looking for me?”
“Bolin was wondering where you were.” She tells him. “I told him I would go find you so he won’t freak out.”
He takes another sip of his wine. “Here I am.”
Both of them remain silent for a few moments, the atmosphere not uncomfortable but not happy either. At the corner of his eye, Mako can see Opal gazing at him and it seems like she’s trying to find her words. Then, eventually, she finds them. “Are you okay?”
“Of course I am.” He lies effortlessly. It comes easy to him. “Why wouldn’t I be?”
He immediately regrets adding that question at the end because he knows what Opal is going to respond with. “You know…because of Korra.”
Mako resists the urge to roll his eyes. Korra this, Korra that. He may still be heartbroken over her but he’s sick and tired of people asking him about it. Can people just drop it?
“‘I said I’m fine.” He stresses. “What she and I had was in the past. She’s happy with Asami now.”
“But are you happy?”
The question catches him off-guard slightly and he looks at her suspiciously, who is looking at him back with an interrogative stare. “What do you mean?”
Opal doesn’t immediately respond, looking uncertain on what she’s about to say, but continues on a few seconds later. “Bolin has mentioned in the past that you seem stressed.”
“I’m always stressed.” Mako counters dismissively. “That’s the price of being a police detective.”
“Is it? Or is it just you?”
His eyes narrow. “I’m sorry?”
The airbending master’s eyes narrow in return, not intimidated by his gaze. “These past couple years you’ve been spending more and more time on your work and distancing yourself from your friends. I get that your job is important to you but there’s got to be a balance.”
“Oh, and you know all about balance don’t you?” He retorts, snorting in derision. “Coming from an Air Nomad.”
Mako knows Opal doesn’t deserve this, she’s only trying to help, but he’s feeling shitty and he’s just sick and tired. Annoyance flashes across her features and she huffs in frustration. “Mako, I’m only trying to help.”
Maybe it's the wine, maybe it's Opal’s stubbornness, maybe it's that he’s tired, maybe it's all of them at once but that’s when he finally snaps.
“Well, I don’t need help!” He exclaims, raising his voice “I’m perfectly happy! Go back to Bolin and tell him he doesn’t need to worry about grumpy, miserable old me! Tell him that the guy who was so unloveable that his own exes got together is feeling fantastic! Tell him that boring, rigid Mako is fine and dandy!”
He is pretty much shouting by the time he finishes but thankfully the volume of his voice is drowned out by the distance and loud celebration of the party. The firebender thought his yells would scare Opal away but he is dead wrong. Stubborn as an earthbender, she continues to stare at him with a stern but sympathetic gaze and remains unintimidated by his outburst. She really is a Beifong at heart.
He also notices when he is done that his vision has been blurred and his cheeks are soaking wet. When he touches his face he realises that he actually started crying during his rant, something that he hasn’t done in a long, long time. Embarrassed, he immediately turns away from the airbender, back facing her, and rubs his face with his arm to rid himself of the tears and to regain his cool and composed look that he had earlier.
“Sorry.” He mutters, not really sure if the victim of his verbal assault can even hear his half-assed apology. “You didn’t deserve that.”
“It’s fine.” Opal says softly, not seeming to care that she was shouted at. “It looks like you’ve been bottling all these feelings for a while. I’m glad that you got it all out.”
Mako actually snorts despite the intensity of the situation. “You really are an Air Nomad. If this was you a few years ago you would have got all up in my face.”
She chuckles and the weight on his shoulders is lifted only very slightly. Still, it's a good change. “You can thank Bolin for that, too. His patience with people has rubbed off on me.”
He chuckles back. However, before he could try to change the topic or leave or do something she continues in a more serious tone. “All those things you said. Is that how you see yourself?”
That question immediately makes the detective tense up. Mako has never been a sensitive person. While Bolin wears his emotions on his sleeves, he conceals them behind a mask. While his brother was unafraid to speak how he was feeling, he rarely speaks his deepest emotions. After what happened with Asami and Korra, he’s afraid of enraging anyone by telling them how he feels.
Because of this unfamiliar territory, Mako’s initial response is a simple shrug of the shoulders as if that would answer everything. However, he realises that he should put in more effort since Opal is trying to help him so he elaborates. “I…I don’t know. I guess. I mean, everyone is making a name for themselves and living their lives to the fullest. Korra is the Avatar and is more beloved than ever, Asami has never been more successful with Future Industries, Bolin is doing well as Zhu Li’s personal assistant, you’re an airbending master, and I’m just…me. I love my job, I really do, but I just feel so…small.”
He takes a deep breath after he finishes, finally relieved that it's over. There is so much more that is needed to be said but right now it’s enough. That’s the most he has talked about his emotions in years. Then, to his surprise, a hand grabs his arm and he is turned to face Opal who is looking at him with so much sympathy and compassion that his heart almost breaks.
“Mako, you’re giving yourself too little credit.” Opal begins softly. “You’re amazing. You make Republic City a safe place to live in for so many people, for so many men, women, and children. While all of us are busy travelling the world, you maintain the balance here and we couldn’t be more grateful. You should be proud of yourself. I hope someday you can see yourself how I and others see you.”
She takes a deep breath and continues. “I know you still love Korra and I know it hurts so badly but I also know that you will one-day find someone who will love you the way you deserve. Because you really do deserve it, Mako.”
Mako’s eyes go wide, his mouth agape, and he is breathless. Her words reach deep into his soul and set it aflame in the best way possible, like a star being born. His emotions that he keeps locked inside burst forth and overwhelm him and before he even acknowledges what he’s doing he pulls her into a fierce, tight hug and hears the surprised “Oh!” from the airbender. A second later, he feels arms wrapped around his neck just as tightly.
“Thank you.” He whispers near her ear and she sighs breathlessly. For the first time tonight, he feels warm…and all thanks to Opal. Bolin really is lucky to have such an amazing person as his wife.
Mako doesn’t know how long they stay in that hug for. Maybe seconds, maybe minutes, maybe even hours, but eventually they pull apart but only by a small margin. They still hold each other as their faces lean back to meet each other, eyes locked in a staring contest between tangerines and emerald-greens.
He’s tipsy. He knows he is because of how much wine he has drank at the party and he suspects Opal is too. And in his moment of intoxication, he can’t help but think of just how beautiful the woman before him is.
Then, in a small haughty whisper the airbender says “Mako.”
And that’s when he acts.
Grabbing the back of her neck, Mako pulls Opal towards him and smashes his lips to hers and kisses her hungrily. He hears an “mmph!” of surprise and for a split second he thinks she’s going to send him flying with her airbending but then he feels her arms wrapped around his neck, her hands grabbing tightly on fists of his jet-black hair, and she kisses him back with equal passion.
In that moment, Mako wonders if he died and went to the Spirit World because in this moment he feels more alive than he has ever been in a long time. They kiss and kiss and kiss, devouring each other like they could die if they separate for even a second. His hands move from the back of Opal’s neck to her waist and he wraps around it in a powerful embrace. Then he feels the airbender’s tongue aggressively force itself into his mouth and he moans loudly at the feel of their tongues battling each other in a deadly fight.
However, when they inevitably separate and gasp for breath they realise what they just did. Their eyes widen in complete horror as they come to the conclusion that they just betrayed the person they care about the most.
Bolin.
“I-I’m sorry!” Mako forces out, breathless. “I shouldn’t have done that.”
“No, you shouldn’t have.” Opal says in a voice just as breathless but then she melancholy adds, “But I shouldn’t have kissed you back either.”
They stare at each other in complete silence, their gazes once full of intensity now full of nearly unbearable guilt. Their minds flash with images of a heartbroken Bolin crying like a never-ending waterfall and they are filled with self-loathing as ferocious as a dragon’s flame.
Mako curses himself, now wishing that he died in the power core of Kuvira’s Colossus all those years ago. His brother saved his life then and he returns the favour by making out with his wife? What the fuck was he thinking?! He’s the worst brother in the world.
“This was a mistake.” He says after a few seconds of intense silence. “It won’t happen again. Bolin can’t know.”
The words spilling out of his mouth almost make him throw up and makes the situation even more fucked up but its necessary. Bolin must never know what happened. Opal seems to understand because she silently nods in agreement, not saying a word.
Eventually, after who knows how long, Mako says, “We should probably go back to the party. They’re probably wondering where we are.”
Opal nods again. She still doesn’t say anything.
When they finally return to the party, Mako just barely resists the urge to wince when he sees his younger brother approaching them with a concerned expression.
“Bro, there you are!” Bolin says worriedly. He places a hand on his shoulder. “Are you okay? Where were you?”
“By the docks.” He somehow tells him in a calm tone. “I was just getting away from the loud noises for a while when Opal found me. I’m fine.”
The concerned expression on Bolin’s face shifts into relief and then transforms again into one of joy, a bright grin spreading across his lips and revealing his shiny teeth. His emerald eyes are full of happiness and that just makes Mako hate himself even more. “Phew, okay! You had me worried for a second! I’m glad you’re fine.”
Then Bolin wraps an arm around Opal’s waist, pulls her close, and kisses her on the cheek. “Thanks for finding him, Opal.”
Mako sees the airbender’s eyes flash with pain for a brief second but then it immediately disappears, replaced by fake happiness along with an equally manufactured small smile. “Don’t mention it, Bo.”
After a few minutes of uncomfortably talking with Bolin, the detective eventually separates from the group to get another drink. He tries to avoid looking at the couple but he can’t help himself. When he and Opal sometimes lock eyes, he can see how much what they did is killing her and his own expression probably mirrors the same pain too.
By the time he returns to his apartment, he can’t will himself to fall asleep. He tries and tries and tries but nothing works. His heart is still racing like it was shot by his own lightning, his palms are still sweaty, and constant fear and guilt rushes through him like a tidal wave. He’s lucky that Chief Beifong gave him a day off tomorrow because he knows he will be exhausted the next day.
And yet, in the darkest corner of his mind, Mako can’t help but remember what happened. He can’t help but remember Opal, her delicious lips, how she smelled and tasted, how she felt in his arms, the sounds she made.
The thoughts are still with him by the time the sun rises.
After that night, Mako swore to himself that this mistake will never be repeated no matter if he secretly enjoyed it. He deluded himself into thinking that it was a moment of weakness brought on by his intoxicated state and it will never happen again. He wouldn’t ruin his brother’s life even more, not after everything they’ve been through.
But that all fell apart when Opal knocked on his door early in the morning the next day.
After a tense, awkward greetings the two of them sat down and talked about in more detail what happened last night. Mako didn’t think they had to because he thought he made himself clear to her after their kiss but he didn’t say anything. Again, they both agreed that it was a drunken mistake and won’t happen a second time and they should just carry this secret to their graves. That was what they agreed to and they should have left it at that.
It didn’t.
Mako can’t remember how it started, can’t remember who leaned in first, but what he does remember is that somehow the two kissed again, then made out on the couch, and then fucked each other’s brains out for the first time in his bed. He hadn’t slept with anyone in a while at that point but what they did was among the best sex he had in his entire life.
And then, just like that, they began their affair. When they were not chatting, flirting, and having sex at his apartment they did it secretly in other places where they could easily get caught. One memorable example was when Asami organised a party at her mansion two months after her and Korra’s wedding. Within minutes of Mako seeing Opal in a new, beautiful dress and her seeing him in his snazzy burgundy suit they locked lips and quickly had sex in a dark cupboard. He silenced her screams with a hungry kiss as he thrusted deeply into her and after that she sucked him off like there was no tomorrow. Even though it was risky, he couldn’t help but find the risks to be exhilarating.
In the early days, they always tell each other that “This is wrong” and “We’re hurting Bolin” and “This is the last time” but over time those phrases went out with a whimper as they knew that despite the overwhelming guilt they will continue doing this because they need each other.
He hates to admit it but it’s true. Opal has been the brightest light in his life and makes him feel happy and loved despite their sinful acts. It’s not just the sex too. There are times where they secretly hang out either in his place or another location where no-one will recognise them and they will have drinks and just…talk. Talk about life, talk about their problems, talk about whatever.
It’s really nice.
Mako was always fond of Opal before they started this relationship but he didn’t really know her. When they first met in Zaofu to recruit her into the Air Nation, he thought she was just a shy, quiet girl, a complete contrast to someone like Korra. But over the years he’s realised that he was completely wrong. Like a Beifong, Opal can be loud and stubborn and fiery when she wants to be and the detective has to admit he finds all of it really attractive.
But she can also be so kind and compassionate and fair. She never judges him for what he’s feeling but also calls him out when he’s in the wrong without demeaning him or making him feel like shit unlike Korra who did that a lot during the final weeks of their relationship.
In return, Mako listened to Opal and her troubles. He listened to how despite how caring and loving Bolin is, he can be very oblivious and ignorant on what she needs both physically and emotionally at times. He also listened to her insecurities, how she felt pressured to be one of the leading figures of the Air Nation. Like she calmed his worries, he calmed hers. They were there for each other like no-one else was before.
Five months into their affair Mako came to the realisation that he had fallen in love with her. In such a short amount of time, the pain he felt for losing Korra’s love evaporated and was replaced by the love he felt for Opal and he was so scared and made him feel even more terrible. He had fallen in love with his sister-in-law, his brother’s wife. A damning situation indeed.
Which leads him to today as thrusts his cock deep inside Opal like it's what he was born to do, like its his purpose in life, panting against her neck with breaths so hot that they threaten to burn her delicious tan skin. Her throat remains spotless, no sign of love bites, as part of the airbender’s design.
“M-Mako!” She screams and then bites hard onto his shoulder, causing him to grunt in sadistic joy.
The firebender grins and whispers right into her ear, “Do I fuck better than Bolin? Am I bigger and stronger and faster than him?”
He knows it's despicable that he enjoys saying dirty stuff like this to his sister-in-law but he doesn’t care because Opal yells “Yes, yes! You’re so much better!” and he feels like he could take on an army of dark spirits.
He can feel himself reach his own peak and he can barely control himself. “I’m going to cum inside you. Do you want that? Do you want me to fill you up?”
“Yes!” She screams. “Please cum inside me!”
And with one final grunt from him and a scream from her, he orgasms violently. He’s high on the sensation of sweaty, sticky skin as he holds the airbender tightly.
For the next few minutes, they stay like this; Opal in his arms, panting against his shoulder and pressed against the wall, and Mako in the crook of her neck. In his post-orgasm clarity, the guilt returns to the forefront of his heart, soul, and mind but, as damning as it is to admit it, he has grown to live with it. It comforts him in a way to know that Opal is going through the same and neither are alone in the sin they are committing.
He’s about to suggest to her to go to the bedroom and begin round two, but then he hears her whisper three words that he never thought he would hear from her.
“I love you.”
He leans back in a flash and gazes into Opal’s olive green eyes, heart beating faster than it was when they were having sex, and drops his jaw. “What?”
Opal swallows and in a louder volume she says, “I love you, Mako. I know I shouldn’t but I can’t help it. I love you.”
She loves him. She loves him .
He smiles. “I love you too.”
Relief flashes on the airbender’s features and she lets out a relaxed sigh and Mako can understand that. He was terrified of how he felt toward her. A part of him still is. There is a high chance their relationship is doomed to fail and hurt so many people, Bolin most of all. He knows that, she knows that. They know they are horrible people.
But Mako can’t bring himself to stop. For so many years he’s made sacrifices. For so many years he’s had to give and give and give without getting anything in return. Just this once, he wants to be selfish. Just this once, he wants to feel loved again.
So, he pushes the guilt down and locks it up until the next time it breaks out and haunts him again. He will deal with it. He always does.
“How much time do we have?”
“I have to teach a class of new recruits in an hour.”
Mako’s smile widens into a grin. “Then we should make good use of the time we have. Do you agree, Master Opal?”
Opal grins in return. “I believe we should, Detective Mako.”
They lunge forward and crash into a powerful, passionate kiss and they let everything go.
Mako is a terrible brother. He knows he is.
But right now? He feels like the luckiest man alive.