Author's Notes: I wrote this late at night. I just felt like writing some Death Note fanfiction and felt that my writing was flowing quite well. I hope you'll agree.
Takes place before Light regains his memories, while they're still handcuffed.
Mortality
It was a combination of white noise and total silence that pressed down heavily on Light's ears. He could barely see, his vision blurred from sleep deprivation. The persistent, goal-driven insomniac beside him was either far too engrossed in his work to notice Light's weariness, or he was ignoring him entirely out of selfishness.
The dull grey light of the computer monitors did nothing to stir Light out of his tired state of mind; it irritated his eyes more than anything else. Despite the superior memory and intelligence Light possessed, he'd spent the entire day cramming endless amounts of information regarding clues and suspects into his head, to the point that forcing any more data would be akin to torture.
The rest of the Task Force's members seemed to share his perspective on the matter, and by the time one o'clock in the morning came around, they felt it was best to head home and sleep so that they may be properly rested for tomorrow's work. Unlike them, however, Light couldn't go home and sleep, resenting the chain between his and L's wrists more than ever. To keep a close eye on his number one suspect was one thing, but to slowly deprive said suspect of sleep was another.
Clearly the detective didn't have Light's personal wellbeing on his mind, even if they were – to some degree – friends. What overruled this friendship was their need to cooperate and work together on capturing the deranged serial killer known as Kira. That came before everything else.
And yet, despite his great desire to find and arrest Kira, Light knew how lack of sleep affected his mental performance. Light required a decent night's sleep so that he could calculate effectively, but that dream hadn't been made reality for several nights. Tonight the weariness was catching up with him, to the point that every few minutes his head would lull forward and he would briefly slip into a doze-like state.
Eventually, L stopped ignoring him, although he didn't look away from the computer screens. "Light-kun, you appear tired." The tone he used made him sound both irritated and bored.
Light peeled his eyelids open painfully, turning to look at L through bloodshot eyes. "Well, aren't you, Ryuuzaki?" He asked, unable to disguise his exasperation.
L didn't blink as he responded, "I suppose I am a little tired." He paused for a moment to take a sip from his half-empty mug of sweetened coffee. "I am tired of finding questions instead of answers."
Light rubbed at his agitated eyes, heaving a sigh at L's response. "So am I, Ryuuzaki. So am I. But can't we just continue researching tomorrow?" Light yawned loudly to emphasise his point. "I'm no use to you at the moment, all things considered..."
There was a minute's pause between the two geniuses as L appeared to be either considering or disregarding Light's comment. Eventually, in a manner that reminded Light vaguely of a haughty child, L tapped on his computer and shut it down. The monitors went blank but still emitted a dark, blue-grey light, and Light's eyes couldn't help but feel relieved at the darkness.
Light was about to stand up and make his way to the bedroom, but after glancing at L, he noted the way that he was still perched immovably on his chair. The thumb on his right hand – the one that bore the gleaming metal handcuff – was sitting on his bottom lip as he nibbled at the fingernail, indicative of his deep contemplation.
He couldn't help but sigh at L's appearance. It wasn't the sheer oddity of the way he sat or the way he chewed his fingernails (Because after spending so much time with the strange man, he couldn't help but get used to L's quirks), but it was the fact that Light knew he still wouldn't be able to go to sleep. Something was plaguing the detective's mind, and he suspected that L might divulge his thoughts soon enough.
Light's head kept falling forward as consciousness repeatedly slipped away, and when L gave no sign that he planned on yielding to Light's wishes, Light tugged gently on the chain to try and get him to move.
Large, black eyes looked at him with an unreadable expression at the movement. "Is there something you need, Light-kun?" L inquired emotionlessly.
Light couldn't help but glare at him, too tired for L's games. "Don't feign innocence, Ryuuzaki. I thought you turned the computers off so that we could go to sleep."
"I did nothing of the sought," L replied dismissively, turning his chair so that he was directly facing him. "A sudden thought had occurred to me, and the information on the screen was irrelevant to this thought." His stare was unwavering, and even in his exhausted state, Light wouldn't back down – he never gave in to that unnerving stare. "To prevent distractions, I simply switched the computers off."
"Well, look," Light began, sounding frustrated, "I'd appreciate it if you would continue thinking to yourself once I am able to lie down." L's expressions always made him wonder if the detective thought he was joking with him. "Seriously. You never sleep anyway, but I do. I don't care if you sit in the bed all night musing to yourself, just so long as I can sleep."
"But I wanted to share my thoughts with you, Light-kun," L said simply, finally breaking his gaze to look down at his knees, pretending to look sheepish. "I thought you would like to hear my thoughts."
"Not at three in the morning!" Light groaned irritably, rubbing at his eyes again to try and keep himself awake. "I'm happy to hear it in the morning, Ryuuzaki. Not now."
L feigned a heavy-hearted sigh. "Oh, but this thought isn't particularly relevant to the case. I might forget it by the morning."
"Not likely..." Light muttered. "Anyway, if it's unimportant, why do you have to share it anyway?"
"Just because it doesn't provide any more information regarding the culprit behind the murders doesn't mean that it's unimportant." L tilted his head to the side, reminding Light of an owl with very, very piercing eyes. "It's about Kira, if that persuades you."
"But it won't add to what we already know about the Kira case?"
"Oh, it will. Nothing important, however."
Light stared at him, half-bewildered and half-annoyed, but finally conceded. He was chained to the guy, so it was hard to win an argument when he could easily persist until it drove Light insane. "Okay, Ryuuzaki..." He made an effort to sound extremely annoyed. "What do you have to say?"
L didn't waste time. Now that he had a chance to talk to Light about his contemplations, he appropriately got to the point. "Originally, I felt that Kira – despite his misguidance in his interpretation of what's right and what's wrong – was a genius. One who matched my own intelligence. Similar to you, Light-kun," He added, which made Light roll his eyes. "Now I find it strange to think anything of the sort. He is intelligent, but in a different sort of way."
"What do you mean, Ryuuzaki?"
"Kira is insane," L revealed, a dark expression taking hold of him. "It's never been more apparent to me than it is now."
"Insane?" Light could barely conceal his snort at L's statement. "Coming from you?"
The corner of L's lip curled downwards a little. "That's a little harsh, don't you think, Light-kun?" He acted insulted, but his blasé tone revealed that he didn't really care whether Light considered him sane or not.
"Eh-heh, I guess it was a little harsh," Light admitted with a light laugh. He gave a wide yawn before he said, "Sorry, Ryuuzaki."
L didn't respond to the apology. "But you see, Light-kun, this is my sudden revelation. It has changed my opinion of Kira entirely."
"You consider Kira to be insane," Light stated, exhaustion still evident in his voice, "But I don't see where this opinion came from." He thought to himself for a moment before adding, "Not that I don't disagree with you. To be honest, I find it quite ironic that someone with that level of intelligence is insane."
"But what's even more ironic," L continued, the computer monitors reflected in his dark eyes, "is the fact that Kira isn't immortal at all."
"And you think he's insane because he equates himself to God, or an immortal being," Light assumed, his wits still about him even though he was progressively getting wearier.
"That's the thing, Light-kun." There was something like eagerness shining in L's eyes as he spoke, obviously pleased with his deduction. "The power that Kira has...the very weapon that he uses to eliminate criminals...it has made him delusional. Insane." L was leaning forward on his seat, staring piercingly at Light. He was perched so far forward that Light offhandedly wondered whether the detective might actually topple head first onto the floor.
"Kira views himself as God," L went on, "but it doesn't make sense for someone of that intelligence to think like that. Someday, whether it is by accident, disease, murder, suicide or age, Kira will die." L narrowed his eyes a little as he said, "He has forgotten his mortality. A man who forgets his mortality is surely insane."
Light closed his eyes and smiled, slightly amused. "Unless Kira just so happens to be a God." L gave him a strange look as he said it. "I mean, maybe Kira's not the kind of God we're thinking of. He's not one with an army of winged angel, or one who created the universe. He's..." Light trailed off, his sleep-deprived mind eating away at his trail of thought.
"You think he's a God of Death," L concluded, no emotion revealed in his words.
Light laughed a little, finding the conversation slightly ridiculous. "No, Ryuuzaki. I'm just very, very tired."
Light fixed L with a curious look when L opened his mouth to say, "Then I have a question for you, Light-kun."
"What is it?"
"Do you like apples, Light-kun?" A small smile crept onto L's face, although Light could see the sinister look in those cold, black eyes.
"Gods of Death love apples," Light stated, glaring at L, his eyes irritated and bloodshot. He was fed up with this late night conversation. "What are you insinuating, L? That I'm a God of Death? That I'm Kira?"
L brushed off Light's anger easily.
"Perhaps. More importantly, however, I hear that apples have more caffeine than a cup of coffee."