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Chapter Text

Osomatsu never stopped smiling. He was never anything but happy, really. Todomatsu had found this odd before, but he couldn't help but wonder about it as he sat scrolling through his social media. Hell, even Ichimatsu showed more expressions than Osomatsu did.

I mean, he did get angry that one time, but aside from that? He’d never seen Osomatsu get sad, or even scared. Once, some creepy puppet guy had kidnapped all of them, and although even they all still had nightmares about it from time to time, Osomatsu had just laughed it off as if it were nothing. 


As he was scrolling through his feed, a bright red and yellow post caught his eye. 


‘!!!12 WAYS TO TELL IF THEY’RE HIDING SOMETHING!!!’ flashed on his screen in violently bright blue and green lettering. Another Buzzfeed advertisement.


But..well, he was bored anyways, so what’s the harm? He knew exactly who he wanted to test it on. 


He started scrolling through the article.

  1. Liars are likely to hide their expressions behind one solid expression.


Yeah, that was definitely Osomatsu-niisan. He barely did anything else!


  1. If you ask them if they’re hiding anything, they’re likely to show a brief flash of another expression before answering! People usually miss it if you’re not looking for these microexpressions. 


Ooh. Interesting. This was something to keep in mind. Todomatsu was hooked onto the article now. 


  1. If you look into their eyes, their first reaction will be to look away.


Todomatsu was nearly full to the brim with anticipation. The thought of finding out something that he wasn’t supposed to know gave him a sort of rush. Was it weird? Probably. Not like he cared. 


He shoved his phone in his pocket before rushing out of the room to locate Osomatsu.



“Osomatsu-niisan!” He called, walking through the doors.

“Yeah, Totty? What’s up?” he called back, not looking up from his manga. 


“I wanted to ask you something.” he said, instantly putting on his most innocent face.

“Sure, what is it?” He said, turning around to face him.


“Are you hiding something from us?” He asked, his voice honey sweet.  He stared Osomatsu right in the eye, and then he saw it. He saw when his eldest brother’s face morphed into the smallest hint of shock before breaking out in a grin. He saw his eyes shift downwards before closing. 


Osomatsu started laughing.


“Oh no! You finally found my stash, huh? It’s fine, you can take from it, just don’t tell the others he said with a wink before turning away again.” He said with a toothy grin before going back to his manga.


Totty allowed his face to fall into a sly grin for a split second before asking Osomatsu a question. “What stash?”


Osomatsu noticeably tensed up, but then breathed a sigh of relief. 


“Oh thank god.” He said with a laugh. “Well, it’s not like i’m telling you now, you know.”


Todomatsu knew that it would be impossible to get any more information from him like this.

So of course, he goes to Dekapan’s.



“Hello! Dekapan, you here?” He called.


“Yes I am! Hello, Todomatsu-dasu, what can I do for you?” he replied, walking out from behind a lab table.


“Hi! I want something that can make someone tell the truth. Ya know, like a truth serum or something.” he said as sweetly as possible. 


“Unfortunately, I’m all out of truth potions at the moment-dasu. But I do have something that can produce similar effects-dasu!” Dekapan turned around, looking through his cabinets for something. 


“Just give whoever you need the truth from this pill! It’ll separate the truth from them and materialize it into real life-dasu. But be careful, this pill will only wear off after ten days!”

Dekapan said as he placed the pouch with the pill into Todomatsu’s hand.


Todomatsu left Dekapan’s lab with a sadistic smirk growing on his face. What could Osomatsu’s secret be? He giggled lightly to himself, a slightly crazed spark lighting in his eye.



“I’m home!” he called into the now full house. He had been out so long that it had fallen dark. Perfect, he could now slip the pill into Osomatsu’s food, and nobody would suspect a thing!


He and his brothers sat around the small dinner table and started to eat the food that their mother had placed out for them. He waited until nobody was looking to put the pill into Osomatsu’s fish. Now all he had to do was wait. 

He watched as Osomatsu unsuspectingly ate the fish, and he couldn’t wait until his big reveal in front of everyone else.

He and Choromatsu-niisan set up the futon, and then he decided to ask the big question.


“Hey, Osomatsu-niisan...what are you hiding from us?” he said to Osomatsu’s back as a devilish grin grew on his face.


“What are you talking about, Tod-” Osomatsu’s eyes went blank, and his face fell slack as he promptly keeled over, and started trembling. 


Everyone’s attention was on them now. 




“What are you talking about Todomatsu?” came Choromatsu’s voice. He could feel Ichimatsu staring from the corner, and Karamatsu and Jyushimatsu ran to Osomatsu’s side.


“He’s hiding something, and I’m going to show everyone what it is~!” He said, his voice sounding a bit more crazed than he would have liked. 


“Osomatsu-niisan’s hiding something?” It was now Jyushimatsu’s turn to be confused. “Why?” 


“I don’t know, Jyushimatsu-niisan. Let’s ask him!” 


Osomatsu lay still on the floor, curled up with his head to his chest. Suddenly, his head jerked up, his scleras black. Black jellylike fluid started to seep from them, forming a figure right next to him. 

Osomatsu's body hit the floor, unconscious as the figure regained color. 


“What the-” came the new figure’s gravelly voice. 


And then Choromatsu slapped Todomatsu across the face, a fury like no other crossing his face, his tone icy, and his brother's behind him.

“Todomatsu, what the hell did you do?”

Chapter Text

It stung. Why did it sting? What just happened? Todomatsu's mind was a blur.

Choromatsu standing over him, cold fury illuminating his face.

Karamatsu was kneeling next to Osomatsu placing cold rags over his head, while obviously panicking.

Jyushimatsu stood, mouth closed and eyes wide but focused.

Ichimatsu sitting speechless, trembling ever so slightly.

There was something else, standing over Osomatsu, too.

But Osomatsu was unconscious? Why was he standing-

"ANSWER ME!" Choromatsu's voice snapped him out of it.

He turned to face Choromatsu, a dazed look seeping through his expression.
"this wasn't supposed to happen."

He let his voice trail off.

Choromatsu released his grip on Todomatsu's collar. Todomatsu hadn't even noticed he was being held up.

"todomatsu. explain what you did, and you better do it quick." Choromatsu didn't sound like Choromatsu anymore. His voice held an iciness, a feeling of pure dread accompanying it.

"Yes, nii-san. But you might want to sit down." His voice was trembling. He was trembling. When had he started trembling? He didn't know. He didn't know anything anymore.

Soon, they were all seated on the floor, on top of the now wrinkled futon. Todomatsu could feel five eyes boring into his skull. Wait- five? Oh yeah. The 'Truth' was here too.

"So i'll start from the beginning.."

He told them about how he had read the article, how he had gone to Dekapan, and about sneaking the pill into Osomatsu's food.

It was at that part Jyushimatsu and Ichimatsu had to hold Choromatsu back from obliterating Todomatsu where he sat. The Truth did nothing.

"you-you DRUGGED YOUR OWN BROTHER, FOR A PRANK!?" he screamed, desperately trying to claw his way out of the arms restraining him.

Todomatsu shrink back in on himself. His cheeks burned. Choromatsu was right. What he had done was despicable.

But there was something bothering him more. The Truth hadn't done anything. It hadn't even spoken aside from uttering barely half a sentence a while ago.

"Choromatsu. Osomatsu's waking up." came Karamatsu's voice. Funny. He had stopped pretending to be painfully cool.

Osomatsu sat up, wincing and rubbing his eyes. He hissed in pain.


"What the hell? My eyes are literally on fire." he groaned as he sat up, rubbing his eyes.

"Well, since you were bleeding black...gunk, i'd say it's not too bad." Karamatsu helped his brother up.


"Wait, what just happened? I can't remember anything-HOLY SHIT WHO IS THAT-" he suddenly yelled as he launched himself away from The Truth.

"Oh, that's the Truth that you've apparently been hiding from all of us." came Ichimatsu's nonchalant voice from the back of the room.



Osomatsu found himself standing directly across from another version of himself.


The new matsu looked unsettlingly like him. He decided that he didn't like this new matsu.

He looked like the dead. Literally.

He had eyebags that could rival Ichimatsu's on a bad day, and his hair was dull. He also looked permanently angry, and his skin was a concerningly greyish color.

His hoodie looked familiar though.

Osomatsu couldn't quite place his finger on where he had seen that hoodie before.

"So. Anyone gonna fill me in?"

His brothers all explained the situation to him, with the exception of his doppleganger, who just stared at him angrily.



Osomatsu's gaze snapped to Choromatsu.

"Did you tell them?"

"No. But I think they should know-"

"Not happening."

Osomatsu stood up, grabbed his other self by his hand, and dragged it off.

It was Karamatsu who spoke next. He had taken off his glasses.

"Choromatsu, what were you and Osomatsu discussing?" it was the question everyone had on their minds.

Choromatsu sighed.

"It's not my secret to tell. Just know that if I could tell you, I would."

Jyushimatsu was the next one to speak up.

"Choromatsu-niisan. I think that we all deserve to know. What do you know that we don't? If you tell us we can all help!"

Ichimatsu chimed in, which was rare.

"You probably don't want to tell us. If it was about anything else, i'd get it. But this is our brother. You have to tell us."

Todomatsu wanted to say something too. But he had absolutely no right to speak. Honestly, he didn't know what he was supposed to do anymore. Was he supposed to leave? Stay? Should he speak, or should he pretend to be invisible?

He decided on staying invisible. It was working for now, at least.

Choromatsu sighed.

"Fine. But i'm going to get Osomatsu, and we'll talk it through with him. I'm not going to do this without him here."

Choromatsu stood up and left, closing the door shut behind him gingerly, as if he were afraid that he'd break it.


He had an idea of where Osomatsu was. It wasn't far.

He slipped on his shoes and stepped out into the humid air.

It was hot.

His sweat clung to his skin as he walked out to the spot just over the hills.

Ah. There they were,

The concrete pipes were exactly as he remembered them, and they were still exactly where they were so long ago.

He walked up to them as quietly as possible, only to be met by the sound of stifled sobs.

He peeked around the corner of one of the larger concrete pipes, to find the Truth standing next to his brother, his brother sobbing quietly. Tears were streaming down his face, his face was blotchy, and his hands were clutching his chest.

It broke his heart to see this again. It had been eight years since the last time he had seen his brother like this.

It had also been eight years when he had changed completely, and Choromatsu was starting to think that maybe it wasn't for the better.

Osomatsu had always been pretty quiet and timid, at least up until they were in high school. Then, by some miracle, he had suddenly changed, becoming more confident, reckless and rude.

That was when he started to drift apart from Choromatsu. They had always been closer to each other than the others, but it all suddenly changed.

It hit him like a brick.

Osomatsu hadn't just drifted apart from him. He had isolated himself, and he had forced himself to change.

He'd been repressing everything.

Choromatsu felt the stone in his stomach sink further, dragging his heart along with it. He'd known what had happened, but he should've noticed sooner.

He'd had EIGHT YEARS worth of chances, and what had he done? He'd missed every. single. one.

And it finally resurfaced to this.

But he had come here for something, hadn't he?

He figured that if he was going to do anything now, he should tell the others. Having Osomatsu around was not going to help his chances of getting that done.

So he walked straight back, looking over his shoulder once more to find Osomatsu now standing still, the silvery light of the streetlamp illuminating his still-flowing tears.
But something had changed.

He looked angry.
And the Truth was smiling.

Chapter Text

“I’m home.” He said, his voice flat, but also like he had been crying.

His green shirt was dripping with sweat.

Ichimatsu has found everything that happened that day a little hard to process. Basically, his older brother gets drugged into revealing a secret, the youngest brother was the root of the problem, and Choromatsu came back from wherever he had been looking like this.

Had Osomatsu done this to him? Or was it the truth? Or maybe it was neither. Who knows. Ichimatsu knew that he probably needed comfort, but he was the absolute worst person you could ask for in that case. Oh well. He’d just have tell the others. 

He crept back around the corner, and started to walk upstairs as silently as he could.

He opened the door to the room , and was about to speak, when he noticed footsteps approaching from behind him. He turned to look at whoever was behind him. 


Choromatsu walked past him, into the room and started to speak.

"I need to tell you all something." came his low voice. 


A few minutes later, they were all seated on the floor, staring at Choromatsu as he began to speak. There was sweat dripping down his face, though it could have very well been tears all the same.

Choromatsu took a deep breath.

"I hope I don't regret my decision to tell you all about this." 

He stopped, fidgeting with his shirt, and then he regained the will to speak. 

"About ten years ago, there was a lodger who came to our house. Do you all remember?"

Ichimatsu didn't. 

"Oh oh! I do! He was suuper fun!" 

Apparently Jyushimatsu did. 

Karamatsu also didn't remember, and for once, he said so without his bone-crushing painfulness. 

Todomatsu didn't say anything. 

It was better that way. He couldn't be trusted to speak right now.

Choromatsu took another shaky breath.

 "Well, he really wasn't. He was a criminal, under pursuit of the government. He hid in our house. But Osomatsu found out. Tougou held him captive. The only reason none of us found out was because he threatened to kill us. Att some point, he started dragging Osomatsu along with him on his crimes. He made him hurt people. He- he tried so many times to tell someone, but nobody knew. I think he told mom and dad at some point. They-all three of them started to show up with cuts and things on their body. Osomatsu's cuts were the worst. He still uses makeup to cover the scars. A few weeks after our birthday, we all got those matching black hoodiu, right? I don't know where they are now, but Tougou used to take Osomatsu's hoodie and make him wear it when committing crimes. It got bad. Really bad. He used to get panic attacks, but he wouldn't make any sound. Sometimes he cried when he thought nobody was looking. And he stopped talking. I found out when I went to go look for him. I found him stuffed down a concrete pipe, with cuts and scrapes everywhere. That's when he told me the majority of the story. Soon after, Tougou left. We never saw him again."

 And then he started crying. Ichimatsu couldn't process anything. Karamatsu was in complete shock, while Jyushimatsu's smile went away completely. Todomatsu was nowhere to be seen.

Nobody spoke, until Karamatsu's shaky voice broke through the haze.

 "L-lets all sleep for today. We'll talk more tomorrow. I think it would be best we process this first."

 The rest agreed. This was too much of a load to think about, and it was getting late. 

But Ichimatsu couldn't help but feel that there was something missing. But..what was it? What was he missing? 


He'd think more about it tomorrow. For now, he was going to sleep.