Chapter 4

“I see. You’re terribly bored, then.” Siesta was surprisingly fearless as she spoke with the hijacker. It felt as if there were invisible blades hidden in their joking exchange. Was this battle about to escalate…? “Yeah, I’m bored. The boredom got so bad that I went and hijacked a flight in a distant foreign country.” “All right, then that’s it.” However, in the next instant— “You hijacked the plane because you were desperately bored.” —she gave her final answer. Without so much as phoning a friend, Siesta played her hand. “…Siesta, wait, just hang on a second. Are you serious?” His motive for the hijacking was—boredom? That couldn’t be right. They’d just been teasing at this grand showdown between a hijacker and an ace detective; this was a punchline. We wouldn’t get away with this. The lives of the six hundred people on this plane were riding on that answer, remember? “Of course I’m serious. The man said so himself, didn’t he? He was bored, so very bored that he hijacked the plane.” “…Yeah, but he was probably just messing with you, don’t you think?” “Oh? Then you’re saying he lied?” “Huh?” Siesta’s eyes turned from me to Bat. “The ace detective frightened him, and he accidentally let something slip. To cover for himself, he’ll say it was a lie to force me to admit a loss and end the game. Thus, we can infer that he’s a coward?” As she spoke, she didn’t show a flicker of fear. “—Ha-ha. Ha-ha-ha. Ha-ha-ha-ha-ha! Amazing! Ahhh, well done. Brilliant. That courage of yours is really something.” Bat started to laugh. It was quiet at first, but gradually, as if he couldn’t fully contain it, he began to guffaw, holding his sides. “Ahhh, I can’t believe it. That’s just insane. Never thought someone would talk me into a corner like that. Well, you got me. I’m beat.” Hey, whoa, are you kidding me? Had he genuinely hijacked the plane just because he was bored? Or had Siesta’s incredibly bold bluff wiped out his will to fight? “That ended faster than I thought it would, but you win some, you lose some. I’ve already achieved my objective, so I’ll bow out here.” Bat got down from the copilot’s body and walked toward us. “Ah, don’t worry. That one’s only unconscious, not dead. I’ll probably get arrested once we reach the airport, but I haven’t killed anybody. If I move into the big house for a while, they’ll let me leave again eventually.” Sighing, Bat sauntered past us, heading back to the seat he’d occupied originally. “All right, wake me up when we land. Oh, and the media’ll be a pain in the ass, so get me a sweatshirt or something to hide my face, wouldja?” Then, just as he was about to make his exit… “My, you really are a liar.” Siesta’s words held no emotion whatsoever. “…What are you talking about?” Bat stopped in his tracks. “Oh, nothing really.” “—Listen here, Miss Detective. You’re right. The real reason I tried to hijack this plane is something else. Out of consideration for your bravery, I’m pretending I lost for you, see? C’mon, don’t make me say everything.” So that really was the case, huh? I thought he’d backed down awfully fast, but apparently he just respected Siesta’s recklessness. If I’d said I wasn’t interested in knowing the truth, I would’ve been lying, but we could have the police figure that out after the plane was safely on the ground. Right now, the important thing was to make sure this guy didn’t change his mind. Let’s just let him return to his seat without disturbing him. That thought was why I was the assistant here. “He’s right, Siesta. He’s responding like an adult, so let’s take a page from his book and go back where we came fr—” “No, that wasn’t the lie I was talking about.” …Oh, I see. I guess nobody who was capable of responding like an adult would be calling herself an ace detective in the first place. “The part where you said you had no qualms about risking your own life in this hijacking. That was a lie, wasn’t it? You were actually scared of dying, weren’t you?” Siesta lit the fuse again. “…What are you saying?” Bat still had his back to us, but he wasn’t moving, and his voice was low. “You backed down too fast.” “From what?” “When you admitted I’d won. Japan has a reputation for airline security; there’s no way a man who would hijack a Japanese plane all by himself, in this day and age, would withdraw so easily because of one girl.” …That had actually been bothering me as well. For having prepared such a huge prop, he’d given up far too easily. I’d been trying to convince myself that we were just lucky, but…Siesta hadn’t let it slip past her. “You were probably executing this hijack on instructions from someone else. In addition, you yourself were ordered to crash and die with the plane. Am I wrong?” “……” His silence indicated that she wasn’t. “But you don’t want to. You’re actually afraid to die, so you used us to give yourself an excuse that would let you survive. Correct?” A hijacker had been given orders to die by somebody else. He’d obeyed the order initially, but when it got down to the wire, he’d realized he valued his life. Thus, he’d come up with the idea of calling a detective and staging a deduction game: By making us guess his reason for the hijack, then aborting the attempt, he’d saved his own life along with the lives of the passengers. “When we reach the airport, the cops will arrest me,” Bat had said, sighing—but that sigh had been one of relief, not regret. If the hijack ended in failure, Bat would be killed by whoever had ordered it. Which was why he’d decided to have the Japanese police protect him until the storm blew over. …Meaning it hadn’t mattered what his reason was. Siesta could have said anything—money, securing a prisoner’s release, a diplomatic issue, or any other reason—and Bat would have thrown up a plausible smoke screen to convince her she’d guessed right. After all, the one who’d most wanted this hijack to fail was Bat himself. …Hmm. But in that case… “In that case, why did he go out of his way to play his game? If he started wanting to give up on the hijack, he could have just surrendered. He didn’t have to pull something like this, did he?” No need to go to the trouble of finding and summoning a detective. All he’d had to do was get off the plane on his own, then turn himself in. “His pride probably wouldn’t allow it,” Siesta murmured. “You didn’t want to lose by default. You wanted to fight and be defeated. Even if it was only an act.” Was that how it was? The man stood there, with his back to us, and he didn’t say a word. Not a single word. “Hey, tell me one thing before the end.” As Siesta and I started back to our seats, Bat stopped us. “How did you know all that?” Finally, having been soundly beaten by the ace detective, the villain of this story asked her why he’d lost. “What gave it away? Was it really just because I backed down too fast, or—?” “Haaah. That was a factor as well, but…” Sounding unenthused, Siesta turned around. “I already knew about you.” “…What do you mean?” “I knew you’d be on this plane today and that you were planning to hijack it. I know about your companions who ordered you to do it. Everything.” …Wait, what? Knowing all that, she’d boarded this flight anyway? Had she known how all this would play out from the very beginning? “First-rate detectives resolve incidents before they even occur, you see. I was just a bit late, since I let myself fall asleep.” Siesta ran her fingers through her hair. Is that where she got her code name? She doesn’t look Hispanic. “…I see. So that’s what it was.” With his back still turned to us, Bat responded to Siesta’s explanation impassively. “Well, I really am glad I asked that one thing, just in case, before the end.” “Assistant, get down,” Siesta murmured from beside me. “The thing is, when first-rate agents find a young sprout, we mow it down before it can grow.” The moment Bat said that, or maybe the moment before, a powerful shock ran through me. “Ow, ow, ow…” The next thing I knew, I was on my butt on the floor. Had something— Had Siesta pushed me? “Hey, Siesta, what the heck was… Huh?” Siesta was right in front of me. Dark-red liquid was pulsing out of her shoulder and streaming down her clothes. Beyond her, Bat was standing still, raking his hair up with his fingers—and from his head, or rather, from his ear, he’d sprouted something like a tentacle with a razor-sharp tip. “Change of plans. I’ll slaughter you and leave the rest.” Mystery meets sci-fi/fantasy “…Ghk.” “Siesta!” I ran to the fallen detective—fallen because she’d protected me. “Rgh, I shouldn’t have hired an assistant… You haven’t been any use at all so far…” “That’s not fair at all! You’re the one who press-ganged me, all right?!” She’s right about me being useless, though! No, but this was no time to be having a petty argument. “What is that thing…?” The tentacle from Bat’s right ear was twisting and writhing as if it had a mind of its own. It was a grotesque color, like what you’d get if you mixed dark green and purple. It seemed capable of stretching and contracting freely as well; there was no telling how wide its range was. “He’s a pseudohuman.” Shakily, Siesta got to her feet, holding her wounded shoulder. “That man is a member of the clandestine organization SPES. They use powers beyond human understanding to create pseudohumans. They’re not publicly known, but they’re a threat to the world.” “Pseudohumans…? That’s insane. Then he’s— Bat isn’t…?” He’s not human? She’s saying he’s a monster? “With him, it’s still only his ear. He merely stole a prototype and forcibly attached it to himself. Basically, he’s a half pseudohuman.” “Siesta, how do you know all this…?” “Then, because he’d betrayed the organization, he was assigned this task as punishment.” “I asked you a question, Siesta! How do you know this stuff?!” Don’t tell me she’s from that other group, too? However, Bat’s deep voice erased that doubt. “You know your stuff, huh?! In that case, taking your corpse back to them as a little memento would be a better plan!” The tentacle streaked toward us again. “Hang on, assistant.” “Huh? …Whoa!” I flew through the air—or rather, Siesta had hugged me to her and leaped out of the way. Her snow-white hair stung my cheek. Her name was Siesta, a nap taken during the daytime—and the sight really did seem as surreal as a daydream. “Are you human?” “Are you stupid, Kimi? Do I look like a monster?” “I’m just saying I wouldn’t be surprised if you were.” “…I’d bet anything you don’t have a girlfriend, Kimi.” But this wasn’t the time for a dumb conversation. With six hundred passengers on the plane, of course people had noticed the racket. “H-hey! Wh-wh-what the hell is that?!” “Eeeeeeeeeeeeeeeeeeeeeeeeeeeeeek!” It started with the people who’d come up here to see what was going on, and a wave of screams and angry yelling began filling the plane. “L-ladies and gentlemen! Please remain calm!” The cabin attendant, whose makeup was completely ruined by now, hastily went to soothe the passengers. But the plane was already in pandemonium. “Argh, if this is how it’s gonna be, I don’t even care,” Bat said. “I’ll just kill every human I don’t need.” “—! Wait, just think about this! If you do that, the plane will crash, and you’ll die, too!” I shouted. “Ha! I’ll let the pilot live. Wait, who are you again?” “I’m the ace detective’s assistant!” Goddammit, now she’s got me saying it. Behold the power of conditioning. “My, you called me an ace detective. What a model apprentice.” “I just said what sounded good. Also, I’m your assistant, not your apprentice.” Argh, really? I did it again. Damn, she’s good. “Seriously, though, what the heck is that thing?” I asked. “You said ‘pseudohuman’ like it was nothing, but…” I was hanging on to Siesta as we evaded Bat’s attacks. “Pseudohumans are monsters created around a core consisting of a certain object. This one fights with his ear, but there are loads of others who fight with their eyes or nose or teeth.” “—You fight these monsters, Siesta?” “Yes, although this is the first time I’ve ended up in actual combat with one. Kimi, you know nothing about the world, do you?” “Hey, no law-abiding middle schooler would know that much about the underworld.” “Perhaps, but you’re a middle schooler flying across the ocean with a mysterious attaché case.” “Wait, how much do you know?!” She’d even had her eye on me? Plus, that attaché case has nothing to do with this business, does it? I swear, I genuinely don’t know anything, all right? “What are these jokers even after anyway? Were they planning to use the hijacking to declare war on Japan or something?” “In Latin, the word SPES means ‘hope’—and their goal is to grant ‘salvation.’ ” As Siesta explained, she took a great leap, still holding me. “Sounds like some sketchy religion…” In the next instant, Bat’s sharp tentacle plunged into the floor where we’d been just a moment ago. We were flying at ten thousand meters. If he put a hole in the body of the plane, this story was over. “I can’t believe a threat this huge to us was hiding out in Japan!” Bat complained. “Any detective worth her salt works in secret. As a matter of fact, none of your companions even knew I existed, did they?” Siesta taunted. She was projecting an aura of cool composure, but as close as we were, I could tell from the way she was breathing that she wasn’t in good shape. She’d burned through quite a lot of her energy. That was only natural. She was fighting while protecting me, and I was deadweight. “Ha-ha! In that case, all your sneaky secrets are gonna be pointless after today.” “Oh? But you can’t go back to your organization, remember? You won’t be able to tip them off.” “Well, I wouldn’t be so sure about that. If I bribe them with information about you, even that short-tempered bunch may have a change of heart.” “You sure it’ll be that easy?” “Ha! You talk like you know.” Once again, like a flying snake, the sharp, writhing tentacle darted toward Siesta. We were on an airplane, with no possible access to any effective weapons, which meant we had to stay on the defense. This was a battle of attrition that we were going to lose. “What’s the matter? You’re breathing pretty hard.” “…I was being careful to hide that.” For the first time, Siesta’s expression clouded over slightly. “Ha-ha, these ears are custom-made. The acoustic cells concentrated in the tip of this tentacle can even pick out the heartbeat of someone a hundred kilometers away.” “…I should’ve gathered more intel. I suppose I really can’t disguise my heart rate.” Even if she was an ace detective, she wasn’t all-knowing. Sweat broke out on Siesta’s forehead. Right now, though, there was nothing I could do. “If I just had a weapon or something…” Obviously, but we were ten thousand meters up. All we had available was what was already here, and security wouldn’t even allow a knife onto a plane. None of the passengers could possibly have anything resembling a weapon in their luggage… No. There was one person. “Siesta, buy me thirty seconds.” “Assistant?” “I’ve got an idea.” Even at a time like this—or maybe because it was a time like this—my mind was running on all cylinders. I’ve been getting dragged into trouble since I was born. Over the course of my life, I’ve survived more ugly situations than I’ve eaten slices of bread. My past experience was telling me this hunch had to be the best solution. “All right. You haven’t been doing anything, so no complaints here.” “Just let me have my moment, wouldja?!” As we lobbed nonsense at each other, I ran hell-for-leather back to my seat. “Move it, move it! Out of the way!” Shoving my way through the passengers, who were clogging the aisles in confusion, I made it to my seat—and hauled that attaché case out of the overhead luggage compartment. Naturally, I had no idea what was in it. I didn’t know whether it would be useful in this situation. Was the cat in the box alive or dead? However, during the carry-on luggage inspection at the airport, I’d noticed the personnel exchanging looks. I’d been concerned about the level of Japanese airport security…but thanks to that, I could take this gamble. “Siesta! Catch!” Running back would take too long; I threw the ridiculously big silver attaché case toward the battlefield with all my might. “Ghk! That’s not gonna happen!” Instead of targeting the bloodied Siesta this time, Bat redirected the tentacle and smashed the attaché case—but as a result, the contents ended up right in Siesta’s hands. And then—Siesta shot the tentacle with her newly acquired musket. “Gwaaaaaaaaaaaaaaaaaaaaaaaaargh!” My bet had paid off. Spraying a grotesque fluid around, the tentacle slithered back into Bat’s ear. Siesta didn’t stop there. She closed the distance between herself and Bat all at once, wrestled him to the floor, shoved the gun against his throat, and— “Bang!” —mimicked the sound of a gunshot. Bat was nonplussed, but Siesta was calm and composed. “There,” she said. “As of now, you’re dead.” Bat shot her a look, obviously wondering what she was talking about. I didn’t know what was going on here, either. So she wasn’t going to finish him off…? “Now your comrades won’t come after you. After all, you’re only a corpse.” “…You little rat. Are you mocking me?” Bat snarled as she withdrew the gun. “Well, you don’t want to die, correct?” “…Ha! After this, that’s off the table. I was going to use you as bait, and you beat me. They’ll bump me off for sure.” “You don’t have to worry. I’ll have the media report that you died here.” “Who exactly are you…?” “I’ll also have the Japanese police shelter you. It’s all right. I have a reliable connection.” Bat laughed with disbelief… Frankly, I wanted to do the same. What on earth was this girl? The word detective was kind of underplaying this, I thought. “If you don’t kill me here, you’ll regret it.” “Why?” “I’m vindictive. I swear I’ll get you back for making a fool of me.” “You won’t be able to.” Siesta got up, releasing Bat. “The red bullet I shot into you a minute ago was made from my blood, you see? Anyone who’s hit with that blood becomes absolutely unable to defy their master. Meaning, your tentacle will never be able to attack me again.” “…How the hell does that work?” “Trade secret.” “Did somebody hire you for this, too?” Siesta smiled faintly. “No—I was born to be an ace detective. It’s how I’m wired.” I see. Apparently, there are people in the world with even worse DNA than mine. Still, that aside… “Sorry to interrupt while you’re putting a neat bow on everything, Siesta, but…” I had major questions about something in that conversation. “That ‘red bullet’ you mentioned—where did you find that sort of time?” I’d thrown the attaché case, Bat had destroyed it…and Siesta had caught the long-barreled gun as it fell, then fired at the tentacle. Was she saying she’d had time to make such a special bullet in those scant few seconds? No, that really wasn’t possible. Meaning the work had to have been done on the bullet already…and Siesta had to have known about it. I had a bad feeling about this. Nonchalant as ever, Siesta said, “I was the one who told them to have you bring that attaché case onto the plane in the first place.” “So you were pulling my strings all along?!” And that was how our dazzling three-year adventure began. Even now, I remember “That was how I met Bat—and the former ace detective.” Lengthy as it was, I’d finally filled Natsunagi in on the old memory Bat and I shared. If I was telling stories from four years ago, there was no way to avoid the topic of my former partner. It had been a long time since I’d talked about her, and while not all the memories were good—for reasons incomprehensible to me—they put a smile on my face. “I see… Okay. I understand your story, but, uh,” Natsunagi said, surreptitiously sidling back, “doesn’t that mean he’s super-dangerous?” She backed up all the way to the opposite wall, trying to put some distance between herself and Bat. “Ah, hmm, well.” “Is that all you have to say? You’re a pretty dangerous character yourself, Kimizuka.” Come to think of it, I hadn’t filled Natsunagi in on my issues with getting dragged into stuff…but she really should have caught on back when she found out I knew people on the police force and in prison. “Also, I don’t want a guy like him listening to my heart…” Well, yes, she had a point. Having that nasty tentacle on her chest could be a devastatingly traumatic experience for an adolescent girl. I wouldn’t want it happening to me, either. “No, no. I can hear your heart just fine from here—and in fact, sweetheart, I’ve already identified it.” Bat guessed what Natsunagi and I were worried about and headed us off. …But what had he said just now? Did he mean he already had an idea of who Natsunagi’s donor was? “Bat, are you saying you’ve met the owner of Natsunagi’s heart?” “Yeah. That was the point of that old story.” It was? The guy was making as little sense as ever. What could that story have to do with Natsunagi’s heart? He wasn’t saying her donor had been in the story, on that plane four years ago, was he? “—Oh.” Behind me, Natsunagi murmured quietly. “What is it? Did you figure something out?” “…Well, it’s just…I thought it was strange.” If we were talking “strange,” Natsunagi had been strange from the moment I met her…but cracking a joke right now would have felt wrong. “You see, I’m not actually the type who does that sort of thing.” “What are you talking about, Natsunagi? You’ve been acting kind of weird for a while now.” “You’re right. I am weird. Sometimes I don’t understand why I do certain things—it’s like I stop being myself.” Natsunagi’s usual composure had vanished, and she was hugging her shoulders slightly. “I mean, I’m not the type who’d do a thing like that to a boy I’d just met.” Was she talking about what had happened in the classroom the previous day? That she wasn’t actually that audacious? In that case, what had pushed her to do it? Well, I had talked to her about something similar the day before. “Memory transference—that’s what you said, Kimizuka. Remember? That means I wasn’t the one who did that. I bet the owner of this heart made me do it.” By that logic, before they died, Natsunagi’s donor could do “that sort of thing.” Someone who didn’t care about shame or their reputation or the means, as long as it was for an end they believed was right. I knew just one person who could pull off such a trick. And that person—had died exactly a year ago. …No. Don’t tell me. A coincidence like that would never happen. That’s just ludicrous. Cold sweat broke out on my forehead. My hands and feet grew numb, and my teeth chattered. Stop it. Please stop. Don’t follow me anymore. I’m not your partner now. Isn’t that right? You’re already dead, aren’t you? “Denial isn’t a good look for you, Watson.” When I looked up, Bat was gazing at me with those cloudy eyes. Like he was telling me not to close mine. “This is the answer.” The sharp tentacle I’d seen that day emerged from Bat’s ear. Still that grotesque shade, as if someone had mixed dozens of paint colors together, and that sickening slug-like way of moving. “Don’t do it, Bat.” “Do what?” “If you kill someone, you’ll hang for it.” “Right. If,” Bat said. “But you know I can’t kill her with this, don’t you?” “Stop!” The tentacle sharpened into a spike, took aim at Natsunagi’s heart, and—a few centimeters before it touched her, the tip crumbled away. That phenomenon triggered a memory for me. It was something a certain someone had said, four years ago: “Your tentacle will never be able to attack me again.” Anyone who was hit with that blood became absolutely unable to defy their master, she’d said. Bat’s tentacle hadn’t been able to attack Natsunagi…or to be precise, the heart that was inside her. That meant— “Siesta, is it you?” The nostalgia I’d felt in that sunset classroom, when Natsunagi had held me in her arms—the trigger had been the heartbeat of my worst and dearest former partner. I’d met her again for the first time in a year. “The moment you walked in, I had assumed that girl was your partner.” Now that he mentioned it, when we’d shown up, Bat had gotten oddly nostalgic… Had it been because he’d heard the sound of his mortal enemy’s heart? Bat couldn’t see, so when he’d heard that heartbeat, he’d mistaken Natsunagi for Siesta. Was that why our conversation hadn’t gelled at the beginning? “When did that ace detective die?” Bat asked, narrowing his eyes. “…A year ago. On a faraway island, in a distant ocean.” “I see. Even if she was an enemy, that’s a shame.” “Yeah. Out of nowhere, just like that, it was over.” “‘Just like that’? Don’t be an idiot. Even after she died, the detective has come back to you.” For a moment, Bat’s words made my chest feel tight. Siesta had come back to me—yeah. That would be poetic, wouldn’t it? If it was true. She’d be the last person to do a thing like that, though. She was a logical ace detective—this theory was too convenient, too trite, too emotional. …Besides, I’d been a lousy assistant. Yeah, I admit it. I’d complained constantly… But really, I knew how incredible Siesta was and how much I was her polar opposite. I was just her shadow, a dark shape following a beautiful girl dancing as lightly as a dream in the bright sunlight. That’s why… That’s why I knew saying that Siesta had come back to me definitely wasn’t right. After all, she would have forgotten me long before now. “It’s a coincidence,” I murmured, but I wasn’t really talking to Bat. It was a reminder to myself. “Running into Natsunagi, and her having Siesta’s heart, is all just—” That was when Natsunagi slapped me across the face. “…Did the heart’s owner make you do that, too?” I asked. “No!” When I looked at her, she was crying. “I did that on my own! I hit you because I wanted to!” Her eyes were red, her face was crumpled, and she erupted at the top of her lungs. “Kimizuka, I dare you to say that one more time! This is coincidence? This reunion is coincidence?! Come on! Why are you being so irresponsible and fatalistic? This is a reunion; don’t brush it off! These are feelings! You were together for three years, and she wants to be with you even after she died! That’s the only wish this little heart has! I’ve been— This heart has been looking for you this whole time, Kimihiko Kimizuka! So it could see you again… Just so it could see you! And then you try to shut it down with a word like coincidence! These feelings matter!” The next thing I knew, I’d run to her and pulled her slim body into my arms. I understand. I see it now. It was like I’d said—the heart inside Natsunagi was searching for someone. “X,” the person Natsunagi had been trying to find for the past year, that Siesta had been trying to find, was…me. Siesta had wanted to see me? “Are you there?” I asked. There was no answer. Of course there wasn’t. The detective was already dead. But… “It’s been a long time, Siesta.” …the warmth of this chest was definitely hers. “Actually, I had a ton of things I wanted to say to you.” How hard do you think life was for me after I became your assistant? I was forced to smuggle a gun, and we wound up in a paranormal battle with a shadowy organization, and our names spread through underworld society, and I ended up having to travel the world with you for three whole years while fleeing from our pursuers; we were flat broke and living hand to mouth while fighting a bunch of pseudohumans, sleeping out in the open during hurricanes, and sometimes on days when we won big at a casino, we’d jump on the bed at a resort hotel together, and then the next day, we’d be penniless again. We traveled across deserts, and through jungles, and over mountains and oceans, and then, and then—