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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?”