I didn’t actually feel the need to go, but I went to the toilet, anyway. Judging by the “open” sign on the knob, the door wasn’t locked. If so, where had Osanai-san gone? She couldn’t have possibly gotten lost in this narrow house which probably wouldn’t take much time to clean, right? I stood in front of the toilet to consider Osanai-san’s whereabouts when I heard a voice from somewhere.
“But if you do that, the volume will…”
“You’re right, but…”
It was coming from the kitchen. One of the voices came from Osanai-san, while the other probably came from Kengo’s elder sister, Chisato. Thinking of taking a peek, I inched towards the kitchen, when the sharp-eyed Osanai-san suddenly spotted me.
Having no choice now that I had been found out, I appeared in front of the two of them. Chisato-san shot me a glance, said, “Welcome” and folded her arms. I’ve known Kengo since elementary school, so I’ve also been acquainted with Chisato-san from that time. I’ve heard that she also goes to Funa High, so perhaps I should call her Chisato-senpai instead of Chisato-san? While Kengo had a squarish face, that did not apply to Chisato-senpai. The only similarity their faces had was that they had distinct facial features. However, in Kengo’s case, that characteristic built up an impression of toughness and strength, but for Chisato-senpai, it made her seem like a flashy person who would probably look good in high heels. Currently, her mouth was in the shape of the character へ.
“…What’s the matter?”
I directed my question at Osanai-san, but it was Chisato-senpai who answered.
“We’ve been challenged by that idiot Kengo!”
I must have looked foolish, for Osanai-san giggled. Chisato-senpai unfolded her arms and pointed sharply at the sink.
“The sink is dry!”
“And the only thing there is a spoon.”
I looked in the sink. As stated, there was only a small spoon there, with a chocolate-colored stain on its tip. Naturally, that would be the spoon used in the mixing of the cocoa powder.
“What about it?”
Chisato-senpai brushed her hair upward.
“You’re slow. Kengo brewed some cocoa for you two, right?”
I wouldn’t say that cocoa is brewed. The word “brew” has the connotation of “immersion”, and is of course suitable for tea, but while it is sometimes used in the case of cocoa, it just doesn’t seem fitting. However, I didn’t say anything. It would be rough to be accused of “having an ulterior motive” again.
“You’re right. How did you know?”
“I told her while we were talking…”
Osanai-san replied in a hushed voice. She didn’t need to be so secretive about it when all she did was tell Chisato-senpai that cocoa was served to us, though.
“If milk was used in the cocoa…”
Chisato-senpai said as she spread her hands wide to indicate the entire kitchen.
“There must be a saucepan here, naturally.”
Ah, I see. You can’t make hot milk cocoa without warming the milk. For that, there must be some kind of pot. It doesn’t need to be a saucepan, specifically. A wok or stockpot would do the job just fine.
“He washed it, didn’t he?”
I bluntly replied, causing Chisato-senpai to point at me without a moment’s delay.
“You sure are slow. As I said, the sink is dry!”
What an excitable person…
Thanks to that frankly depressing conversation with Kengo, my feelings were a little hurt. And here was Chisato-senpai with her high amounts of energy, which somehow made me feel better, something that I didn’t expect myself. A wry smile rose up on my face as my melancholy largely dissipated. They say that smiling is good for one’s health, and it seems that the type of smile doesn’t matter.
“To make hot milk cocoa without wetting the sink… do you think that’s possible?”
“Who knows? Perhaps Kengo came up with an ingenious plan?”
“So if I were to ask you to do the same…”
“Me too. Neither can that girl over there.”
Being pointed at, the “girl over there” responded with a small nod. Chisato-senpai brought her hand that she had used to point at Osanai-san into a fist and shook it.
“Kobato-kun, right? You’ve known Kengo for a long time, haven’t you?”
“Doesn’t it frustrate you that Kengo can do something that you can’t?”
“You’re right, it is frustrating.”
I replied on reflex, but immediately regretted it. I’d accidentally revealed my true colors. Osanai-san let out a low, sharp voice.
On the other hand, Chisato-senpai seemed satisfied to no end.
“Exactly, exactly. If so, how about tracing Kengo’s actions with me?”
That was certainly a strange turn of events. That said, I couldn’t swallow what I had already spat out. Anyway, Kengo couldn’t have possibly come up with a plan that I can’t figure out by racking my brains for a bit. I should try solving this puzzle with her.
In any case, it wasn’t even a difficult puzzle. All I had to do was find a way to heat up the milk without using a saucepan. While the kitchen wasn’t spacious, it was complete with electrical appliances. And of course, it should have that.
I looked around for it, and found it, as expected. I was, of course, referring to the microwave. It was larger than I thought it would be.
“That’s a big microwave.”
I remarked. Chisato-senpai puffed her chest out in pride.
“You can make sweets in this. It works as an oven, too.”
I noticed Osanai-san looking at the microwave enviously, while seeming to hold herself back.
“…It looks like you can even fit a size 8 sponge cake1 in this microwave.”
“So you’re thinking that he heated up the milk with the microwave, aren’t you?”
While I was a little irked by her mocking tone, I nodded.
“If he used a microwave, he wouldn’t need a pot.”
“In place of that, he’d need a non-metallic container, though there’s all sorts of things here made of plastic or ceramic, like that bowl over there. But as I said, you’re slow. This is the third time I’m saying this, but the sink is dry.”
I see, so there’s no big difference, huh.
Then again, he didn’t have to heat the milk up in the same container. I raised three fingers.
“How about this, then? He prepared three coffee cups, filled them with milk, then put them in the microwave. He would have three cups of hot milk.”
However, Osanai-san quietly put in a word of advice.
“But Kobato-kun, what we received was not hot milk…”
“Yes, it was cocoa. So he added cocoa powder from the top with a spoon.”
“But Kobato-kun, what we got was not just normal cocoa…”
So what, I was about to ask, when it hit me. She was right. We were not served just normal cocoa, but delicious cocoa, and we’d just listened to the method of making such delicious cocoa. It required adding only a small amount of milk.
In other words, he must have needed some equipment for pouring out the milk into the coffee cups which contained the final product, cocoa.
And yet the sink was dry. Without thinking, I let out a sound.
Chisato-senpai folded her arms.
“It seems that you’ve finally recognized the problem. Just what did that idiot Kengo do? Even if he didn’t use something like a bowl, or in other words if he placed coffee cups in the microwave, there should be six cups.”
I noticed a small mistake, so I corrected her.
“No, he could have done it with just four cups. He warmed up three cups of milk, then prepared another cup for making delicious cocoa. He dissolved the cocoa powder in that cup, resulting one cup of cocoa, and one empty cup. By repeating that three times, he would produce three cups of delicious cocoa.”
But I was corrected once again.
“That’s impossible, Kobato-kun. The spoon would get wet when he makes the first cup of cocoa. He has to scoop cocoa powder out of the bag three times, so there should be two spoons in the sink, but…”
It seems that Osanai-san is going along with Chisato-senpai’s puzzle and my obstinacy, even though she probably isn’t very eager about it. In my heart, I pressed my hands together in gratitude.
“Also, we’re talking about Kengo here. He definitely wouldn’t do something as sloppy as inserting a wet spoon into a bag of cocoa powder. If that’s not it, he could have prepared one cup for heating up the milk and three cups with cocoa powder, so he just has to heat up the milk and pour it into the another cup three times.”
However, this means that he used the microwave three times, which is quite a waste. That can’t be it.
Chisato-senpai shook her head in an exasperated manner.
“You guys sure are unproductive. No matter which of your theories is right, he would have to use four cups, right? But only three cups were used.”
Oh, right. I tilted my head.
However, that conversation was definitely not unproductive, because it helped me see the direction to the correct solution. I mumbled to the two of them.
“Hmm, the way I see it, we can solve the problem if we look at it from another perspective.”
“Look at it from another perspective? What do you mean?”
“Well, I originally thought about it this way: The end result is three cups of cocoa, so there has to be some equipment for pouring milk in, so why can’t we find it? But currently, we can look at the question like this: Given three cups of hot milk, it is necessary for some mortar-like equipment for mixing the cocoa powder to exist, but why is there no such equipment? Now, we’re looking at the question from another perspective.”
A meaningful smile appeared on Chisato-senpai’s face. That was curious, but I was a lot more strongly attracted to the problem that I’d been given.
Hang on. By the previous line of reasoning, four containers are required for three cups of cocoa, but in reality there were only three containers.
“Perhaps this is what happened.”
The two of them focused their attention on me.
“Basically… there were only two cups of ‘delicious cocoa’. The other cup was made by dropping cocoa powder into hot milk, and was conventional, powdery cocoa. How about that?”
That way, whichever one of the two methods Kengo used, he would end up with two cups of delicious cocoa and one cup of normal cocoa.
“I see,” Chisato-senpai replied. However, Osanai-san looked around in the air, then sent a weak gaze in my direction. She wanted to deny my suggestion, but was too shy to do so, I suppose. Why would Osanai-san do that? I thought, and instantly hit upon the answer.
“No, sorry, that can’t be it.”
“Why not? It’s entirely possible that Kengo made his own cup of cocoa sloppily, isn’t it?”
“You were not there, Chisato-senpai, but the each of us randomly picked a cup from the tray, and Kengo was not the first to take his cup.”
If there was some kind of magician’s secret behind it, Osanai-san and I could have been steered towards the correct cups. However, that would be like using a chef’s knife to kill a chicken, and there is absolutely no need to utilize such techniques to distribute cups of cocoa. Anyway, I can’t imagine Kengo having the finesse to pull off such a move.
That means that three cups of cocoa must have been made with only three containers.
Hmm, Kengo, what exactly did you do? You haven’t shown me your clever side before.
The silence continued. The phrases “three cups of cocoa” and “delicious cocoa” kept repeating in my mind. Before my brains turned into cacao, Osanai-san murmured.
“It’s possible to make three cups of cocoa with two cups of hot milk…”
Chisato-senpai and I turned to look at her in surprise, causing Osanai-san to momentarily panic and look around at her surroundings, probably searching for cover. However, we were in an open kitchen, so there was nowhere for her to hide. In exchange, she shrunk back and looked down, then continued in a small voice.
“He put two coffee cups of milk in the microwave and got two cups of hot milk. He took one more empty cup, and dissolved the cocoa powder in that cup to make two cups of delicious cocoa. Up till here, it’s the same as what Kobato-kun suggested in the beginning. After that, he poured one third of the cocoa in each cup into the empty cup. That way, he gets three cups of delicious cocoa.”
I see. However…
But Osanai-san voiced my rebuttal on her own.
“However, if that was the case, the cups would have been filled up only to the sixty-six percent mark, while the three cups we got were all filled to the brim…”
“If you knew that it was impossible, then why did you even say all that?”
Osanai-san face turned red upon hearing Chisato-senpai’s reasonable criticism.
“I was just trying to fill the silence…”
That’s heroic. Too heroic.
As my heart was moved into tears, Chisato-senpai suddenly made an exclamation.
“Ah! I got it! That’s it, it’s exactly like what the midget said!”
Osanai-san muttered, apparently dissatisfied with the nickname. Not caring about that, Chisato-senpai spoke excitedly.
“With that method, he would get three cups of cocoa using three cups. All that is left is the volume, meaning that he made three cups of thick cocoa in advance, then added milk to them.”
I immediately objected.
“That would cool down the cocoa. The cocoa that we received was so hot that we couldn’t immediately drink it.”
“He could have put them in the microwave, then. They’d become hot.”
…Well, it’s certainly not impossible to make three cups of delicious cocoa in three containers using this method. However…
“So he heated up two cups of milk, made cocoa, split it into three cups, then heated the cocoa up again. That takes too many steps.”
“He was challenging us.”
“I don’t think so. I can understand if he had asked us to guess how he made the cocoa, but I can’t imagine him going through all that trouble for something that he wasn’t even trying to show off.”
Chisato-senpai groaned, then fell silent. Once again, she folded her arms.
“With this, I can also make three cocoas with three cups, but it really pisses me off that it’d be less efficient than how that idiot Kengo did it. Ah, seriously, why does cocoa have to come in powder form!”
Those words came out as just an outburst of frustration, but they got me thinking.
“I see! What the heck, I might have misunderstood.”
“Yes. I assumed that Kengo made cocoa from cocoa powder, but what if there was some kind of cocoa solution that I didn’t know of?”
Chisato-senpai’s shoulders drooped. She languidly walked over the fridge and opened it. On the other side of the door, below the eggs and beside some packs of milk, was a cocoa-colored bag.
“That’s the cocoa powder. It’s the normal kind.”
Osanai-san added, “It’s Van Houten.”
She was right. That was certainly normal cocoa powder.
“So why is it in the fridge?”
“It’s to keep it dry, right? That’s what I think, anyway. That was what Kengo did, so there shouldn’t be any deep thought behind it.”
Ah, I see. I’ve heard that rice crackers don’t go soft if you store them in the fridge. Although I feel like I’ve also heard that that doesn’t apply for refrigerators today.
Anyway, now we know that the ingredients of the cocoa did not possess some kind of secret that cannot possibly be known to others. Hmm, I think that means we’re stuck.
Hesitatingly, Osanai-san made a suggestion.
“If you don’t know and want to know… isn’t it better to ask Doujima-kun?”
Chisato-senpai’s response was immediate.
I couldn’t declare it so clearly, but I held similar feelings. While it was partly for fun, we’d come all this way, only to get stuck here. Is there really no breakthrough we can make? It’s not like Kengo used magic, either. We need to find a way to compress four containers into three. Is there any magic that can make a bullet hit two people? The question I posed earlier, “Given three cups of hot milk, it is necessary for some mortar-like equipment for mixing the cocoa powder to exist, but why is there no such equipment?” is framed weirdly; it seems to hold some kind of unnecessary preconceptions.
Osanai-san looked at me while I was deep in thought.
At the same time, Chisato-senpai paced around the kitchen.
“Why is the sink dry? The cups and spoons are dry, too. Did he wipe off all drops of water from them? But he left a spoon…”
The sink is dry. For someone in the same household to be so fixated on that point, there should be no dishwasher that we cannot see.
I stared at my feet and submerged into my thoughts. Not because I was accompanying Chisato-senpai, and of course, not because of any rivalry towards Kengo, but because thinking was fun.
The sink had to be wet, because it had to be used to wash and dry the fourth container, for the purpose of making us believe that it had not been used for making cocoa. However, it was impossible that Kengo would wipe off the entire sink just to camouflage it from us. If he hadn’t used the sink, then the fourth container would still be wet, but if it were still wet, there was no way that it wouldn’t be noticed.
“If it’s wet, there’s no way it wouldn’t be noticed.”
I tried vocalizing my thoughts, because I felt that I could organize my thoughts that way.
“Basically, the problem can be rephrased as such: ‘Making three cups of delicious cocoa produces four wet items. What is the fourth item?’ There are three coffee cups wet with cocoa. If the other item was washed, it would be wet with water. If it wasn’t washed…”
There’s no mistaking it. Exactly, this is it. Now, the problem has been properly rephrased. The answer is now clear.
I raised my head spiritedly.
“Please open the refrigerator.”
While bewildered by my sudden burst of vigor, Chisato-senpai complied. Will this be fine? Given the time taken, I believe that evidence should still remain.
“I’ve opened it. What should I do now?”
I pointed to one part of the refrigerator.
“Please hold that pack of milk.”
As I requested, Chisato-senpai touched the pack of milk, and suddenly drew back her finger. “Ah!” a sound leaked out her mouth as she felt an unexpected sensation.
“It’s hot, isn’t it?”
I was hit with a wave of liberation, then a sense of achievement. I felt a smile forming on my face, but repressed it.
Kengo put the entire pack of milk into the microwave and heated it up. Since the microwave can bake a cake, it should be large enough. Something surrounded in metal will not be heated up in a microwave, but if you think about it logically, paper will not block microwaves. What is the fourth wet item? The answer is the pack of milk itself.
I looked up at the ceiling, and let out a deep sigh.
Chisato-senpai raised her fist and shouted.
“That sloppy idiot!”
Editors (Tier 2) : Joshua Fisher, Slush56, Jen Murph, _Maki
Assistants (Tier 1) : Karen Kronenberg, Definitelynotme, Rolando Sanchez, Kevin Kohn, Jaime Cuellar, Yazmin Arostegui
Thank you very much for all your support!