#I read a collection of tachiiatsu fics and here we are

[starlightshadowsworld]

Bsd except the baby Atsushi saved and left with Tachihara (in chapter 29 of the manga) ends up being raised by them both.

Atsushi going back to help clean up the wreckage caused by the Guild. And finding Tachihara trying to calm the kid.

Feeling bad for just leaving him like that, Atsushi rushes over and successfully calms the kid down.

Tachihara looks at him in awe, because how the fuck?

Atsushi explains that back at the Orphanage the older kids tended to look after the younger ones.

Seeing that everyone else has been paired off, Atsushi asks if Tachihara wants to join him and he agrees.

Doing their jobs for the remainder of the day and keeping the kid company.

They aren't able to find the kid's guardians and so Atsushi decides to take them home for now. Not wanting to leave the lil guy alone.

This routine goes on for a while, Atsushi starts looking forward to spending time with Tachihara.

They talk about anything and everything, except their jobs.

At some point Atsushi tracks down that the kid's parents died in the incident and their families want nothing to do with the kid.

The kid would be given up to an orphanage, and given the nearest one is Atsushi's orphanage.... He ends up taking the kid in.

The kid is a lil baby boy called Kisho (named after the student in irl Atsushi Nakajima's Legend of the Master)

Returns home after the papers are signed and has a freak out because oh fuck I'm a dad?! I can't be a dad!

Kyouka talks to him, having known all about this from day 1 and tells him he'll do great. Given he's already doing a good job.

And determindly says she'll be the best aunt in the world.

Tachihara is completely on board with it when Atsushi tells him. And says he's gonna help out too.

Tachihara: Hey, you ain't alone in this. I've got your back.

Atsushi: You do?

Tachihara: Duh, you ain't getting rid of me that easy, weretiger. Me and you we're gonna be the best damn parents this kid can get.

Atsushi: smiles Yeah, yeah your right!

Kyouka, looking at them both like "I know what you are."

Atsushi falls first.

But Tachihara falls harder.

Both are in denial.

The Agency found out after a week.

Ranpo deduced it when he noticed Atsushi falling asleep at his desk and got concerned.

Telling Kunikida to let Atsushi rest before the other can try and wake him.

Ranpo does leave a packet of sweets he liked as a kid on Atsushi's desk.

Atsushi was afraid what the others would think of him but Kyouka encourages him to tell them.

It went well. Everyone is surprised (minus Ranpo) and teases him over being a dad. "Oh our Atsushi's all grown up!"

But they make sure he knows that they had his back.

Fukuzawa: emotional I have a Grandchild?

Atsushi: You...You see me as a son?

Fukuzawa: Hugs him close Of course I do.

Atsushi: Sobs into his arms.

Yosano appoints herself as Kisho's personal doctor, saying she'll give him a check up and make sure he's healthy.

The next day Atsushi brings Kisho to the office and everyone gushes over him. Fukuzawa cries, again after being able to hold him.

Naomi took several photos.

Dazai is a bit taken aback when Atsushi let's him hold Kisho. He was afraid he'd accidentally hurt the lil guy.

They have some staring contest before Kisho starts laughing and Dazai just internally melts.

Dazai: I've had Kisho for 5 minutes but if anything were to happen to him. I would kill all of you and than myself.

Kunikida makes a schedule so that Atsushi isn't overworking himself and that when he has a mission there's someone to look after Kisho.

He questions how Atsushi's been managing so far. Atsushi's just like "Oh Tachihara's really been helping me out.

Pause.

Everyone seeing Atsushi visibly light up and talk about how he and Tachihara found Kisho.

And how he's been visiting and watching over for Kisho when Atsushi's at work because he mainly operates at night.

Everyone: thinking These bitches gay.

And scheme to set them up.

Meanwhile the Port Mafia finds out in like 5 minutes.

Because Tachihara was texting Atsushi during game night and Gin asked what was making him smile so much.

So he told em all.

Akutagawa:....

Tachihara: Is he, okay?

Gin: Give him a sec.

Akutagawa: I'm an uncle?! How could you not tell me I was an uncle?!

Tachihara: emotional cos Akutugawa also sees him as his brother.

They tease him a whole bunch because they can tell he's got a crush on Atsushi but Tachihara's like pfft nah.

He totally does.

Chuuya: Soo when do we get to meet the lil guy?

Tachihara: texts Atsushi They're both coming over tomorrow, he said you can come meet Kisho.

Akutagawa: Very well, I will... Tolerate the Jinko for now.

Everyone looks at him in shock.

Atsushi is hesitant but he warms up to everyone.

Akutugawa and Gin fight over who gets to hold Kisho while Chuuya and Kouyou are already planning on spoiling him.

Atsushi: Akutugawa! Stop coming in through the window!

Akutagawa: It's not that big a deal okay, now where is my nephew?

Atsushi: It's a huge-... Why do I even bother? Here hands him Kisho.

Gin: appears at the door You!

Akutagawa: smug Me!

Atsushi and Tachihara: catch each other's eye and laugh.

The entire alliance between the Port Mafia and the Agency lays on the foundation that no better hurt Kisho.

Or else.

The Cannabalism arc in this just goes straight to everyone working together.

Atsushi realises he likes Tachihara and with his friends help, plans a day out and confesses.

Only to get rejected.

Tachihara:... Listen, now that the Guilds been taken care off and the virus is taken care off we don't need to keep pretending.

Atsushi: Pretending? What are you saying?

Tachihara: Do I have to spell it out for you? All of this, was just me following orders so the Port Mafia didn't mess up the alliance with the Agency.

Atsushi:... Oh... Tears in his eyes Right, yeah... Of course. I'm sorry for wasting your time than, I'll be out. Come on Kisho, say goodbye to your da-... Tachihara.

Leaves.

Tachihara: cries

Because Tachihara realised he'd fallen for Atsushi too. But knew the mission was more important.

His orders made him who he was, he can't throw all that away.

... No matter how much it hurts to watch the smile fade from Atsushi's face. The tears to well up in his eyes as he leaves.

Tachihara doesn't go after him, even if every part of him wants too.

Everyone notices a change.

Atsushi shows up late. Kunikida stops mid lecture the moment he sees Atsushi's tear stained face. Kisho is in his arms and he's lead to the sofa by a concerned Junichiro.

Junichiro: Atsushi sits beside him what's wrong?

Atsushi: It wasn't real... It wasn't, not to him. He was just following orders and... I'm so stupid.

Kyouka: murderous intent.

Tachihara is silent. He doesn't banter with the other Black Lizards not even Gin. He's brutal in his fights in a way he's never been and it's concerning.

Gin: Hey, talk to us what's gotten into you.

Tachihara: Nothing, I'm fine.

Akutagawa: Did some happen with Kisho?

Tachihara: No, no he's fine. Can we not do this right now...

Gin: Alright... but, we're here for you.

Tachihara: sad smile thanks.

They don't learn what happened until Akutugawa and Atsushi end up on a joint mission.

Akutagawa is so confused because he saw how happy Atsushi made Tachihara.

Akutagawa: Somethings up with him, this isn't right.

Atsushi: Akutugawa, it's okay.

Akutagawa: Jinko, I care for Kisho and I have grown to care about you. And I know Tachihara, he would never do that to someone he loved pauses... I mean.. Cares about.

Atsushi: shakes his head No... The Headmaster was right, I wasn't made to be loved. Who could love a monster like me?

Akutagawa: Do you want the list alphabetically? Chronologically? I will get hand written letters from all of your friends, I'll do it.

Atsushi: sad smile What did I do to deserve you as a friend?

Akutagawa: rolls his eyes, affectionate You didn't need to be anything but yourself. But your adorable child and cooking skills definitely helped.

But things stay as they are, with Atsushi and Tachihara both feeling the others absence in their lives.

As does Kisho who looks around for Tachihara and lights up only to look sad when it's not him at the door.

Atsushi misses the way Tachihara could brighten up a room without even trying. How Tachihara told the worst jokes just to get Atsushi to laugh.

That Tachihara would watch horror movies and than hide his head in Atsushi's shoulder whenever a jumpscare appeared, and than deny it.

Tachihara misses the way Atsushi was a calm presence in the chaos of his life. How Atsushi looked at him like he was his whole world.

That Atsushi would fall asleep beside him because he knew he was safe with him.

And than... Jouno arrests Dazai in broad daylight and the Agency are on the run.

Tachihara assuming his role as the 5th Hunting Dog.

He's under the influence of the page and yet his heart hurts seeing his friends get hurt by his hands.

Everytime Fukuchi talks about the Agency falling, all Tachihara can think, 'is Atsushi okay?'

It eats at him... until one day he walks into the Port Mafia and is told Akutugawa is gone.

He's lost another big brother.

The weight of it all hits him like a truck and he can't breathe. Someone's talking to him, someone's at his side and it's Atsushi.

And Tachihara knows he doesn't deserve this, knows he doesn't deserve Atsushi's kindness and yet he caves.

He's fallen, he fell so long ago and here is his tiger holding him like he's his whole world.

His tiger that he hurt.

Tachihara: I'm sorry... I'm so, so sorry.

Atsushi: It's okay.

Tachihara: No, no it's not. I lied, it was real. I was just too much of a coward to admit it and I hurt you... But it will be, I'm gonna make this right.... If you'll let me.

Atsushi: I won't lie it hurt, a lot. But what hurt the most was being alone, was feeling like I'd lost you.

Tachihara: I'm not going anywhere. And I'm never leaving you again.

Atsushi: tears up hugs him

Tachihara: hugs him back soo does this mean you wanna be my boyfriend?

Atsushi: snorts Obviously.

Kisho crawls to him and Tachihara holds him close "hey lil guy, you miss me?"

He had everything and he threw it away... Not anymore.

Tachihara reveals everything that he knows and is shocked to learn that wasn't all. As the news of the Decay of angels hits.

That Fukuchi hurt Atsushi and took Akutugawa as a pawn because suprise, vampires exist now.

Tachihara: fussing over Atsushi He didn't hurt you did he?

Atsushi: Well he cut off my leg but-

Tachihara: I'm gonna kill him... I'll fucking kill him.

Just seething rage.

Atsushi is also angry about everything Fukuchi's done but the look he gives Tachihara is nothing but fond.

He missed him.

Tachihara notices said look and just blushes bright red.

Gin: Ay lovebirds as cute as this, we've got a world to save.

Tachihara manages to get amengozen away from Fukuchi and hands it to Fukuzawa.

He won't kill him, he won't lose anything else to this man ever again.

He ends up getting injured in the process but not nearly as much as he would have.

Because he's not alone.

Atsushi is right there with him, never left his side even for a moment.

Even managed to swipe Fukuchi's eye.

Atsushi: That's for Akutugawa you bitch!

Tachihara: proud boyfriend smile.

Fukuchi is taken care off and the world is saved.

Both of them hold each other, barely able to stand but their smiles are nothing but relieved.

And they kiss.

Akutagawa, now mortal looks down at them both like it's about fucking time.