CHAPTER 2: Ryuk
From the beginning, it was always nothing special. It was simply what everyone did. Find a human, write their name, and, if curious, watch them drop 40 seconds later. Bothering to write a cause of death was rarely done.
You didn't even need to go to the human world to do it. There were convenient viewing stations, catering to shinigami laziness and decadence.
Ryuk often wondered how far things would degenerate in the future. The shinigami realm was rotting; that was clear to everyone. Writing names was meaningless but needed. There was an instinct to avoid death, perhaps a fear of the unknown, for there was nothing, probably nothing, after death.
If there was something after death, shouldn't a god of death know about it? No, there was only non-existence to look forward to, and that was simply more meaninglessness.
Other than writing names, there was little to do, only talking with the others (but really nothing to gossip about), wandering around (but nothing ever changed and the landscape was bleak), eating (but the few withered apples he could find were dry and sandy), playing games (boring games that could go on for decades), and the most pitiful form of entertainment of all: sleeping.
Writing names was sustenance only for the purpose of sustenance, and when Ryuk wrote he rarely felt anything.
Sometimes there was a bit of interest in watching the human world for a while, a place so unlike the shinigami realm, so busy and full of purpose, and Ryuk would almost feel a twinge of regret at writing down some poor sucker's name. Watching them die wasn't as entertaining as watching them alive.
Still, there was no reason to keep them alive. There were always more of them, such multitudes it was astonishing, and their lives were rather alike. The typical human lived in a building, slept at night, had some sort of job or household duties that took up much of the day, gradually became older, and all too quickly died anyway.
Humans were more entertaining alive than dying, but not by much, not even slightly enough to battle the gnawing boredom that weighed on Ryuk's mind constantly, making him restless, a deep yearning settling in his gut.
The plan he at last created also brought him his first writing-related smile in a long time. It was the giddy lightness of an adventure about to begin, of real hope blossoming in his heart. Things would be different, for a while, anyway.
Ryuk even bothered to write down causes of death, as he fueled himself with enough lifespan to outlast any human who might pick up his notebook. He laughed as he watched the four young construction workers he'd picked fall to their deaths, the first to fall tangling the second and pulling him over the edge through sheer panic, the third and fourth dying in the process of trying to save the first two.
After that, it was a long time until he wrote another name. Following Light Yagami around was an immense source of entertainment, better than he'd hoped for. The battle with L was simply delicious. Humans were so interesting, and there wasn't any need to write names down.
But, after L died, through Light manipulating Rem into killing L and herself, it got boring for a few years. Light without a worthy challenger was simply not the same.
Sometimes, then, Ryuk was tempted to write. He'd perch on top of the building Misa and Light lived in, take out his death note, place pen to paper and simply think. Writing Light's name would end the entire adventure and he could go home. Tempting, tempting, but he couldn't quite do it.
That would be anti-climactic, not a proper ending at all, and the shinigami realm was sure to still be phenomenally boring. Light had produced a lot of entertainment, and perhaps the current lapse in fun would go away.
The other temptation that nagged Ryuk during those times was to kill someone to make trouble for Light, to try to restart the furious chase and force Light to use his genius mind to evade capture. Ryuk didn't do it because he couldn't think of any other plan than killing one of Light's fellow investigators, and that would probably backfire badly. Light and Misa weren't being very careful any more. One good, thorough search of their apartment would expose their guilt, and that would be an unsatisfying ending too.
His own notebook remained unused until the very end, until Light was panicked, cornered and wounded in the Yellow Box warehouse. Light's last command sparked anger in Ryuk's heart. The order to kill all the investigators, it was a suicide order.
It was the worst possible insult, after being given years of boredom and treated like a household pet and even made to run errands for Light. Killing to save Light was forbidden; Light knew that better than anyone. Light was so arrogant that he thought a shinigami should die for his cause, yet another one after Rem.
Humans killing shinigami, that wasn't right. It wasn't right at all, it was horribly twisted.
"Yeah, I'll write," Ryuk replied.
Ryuk took out his death note and began writing a name in it for the first time since before meeting Light, enjoying the shocked silence and panicked faces around him as Light beamed his trademark smug smile from his blood-spattered position on the floor and even began boasting, gloating over the others.
It was the last piece of entertainment Light would give, and Ryuk savored it deeply.
I'm not a fool like Rem, and I'm not one of your fawning minions. You forget I'm a god of death. This should remind you.
It was a thrill, to trick Light and put him in his place, to do a dramatic reveal of what was really being written.
Holding it up, Ryuk said, "Nope, Light. It is you who is going to die."
Light Yagami
It was worth it, to see the reactions, to see Light shocked at his own mortality, the mortality he should have known all along. For the first time, Ryuk felt that writing a name had been truly meaningful.
A/N (Author's Note):
This chapter's ficlet is obviously based on the manga ending rather than the anime ending. Although the manga doesn't explicitly spell it out, I believe that Ryuk must have been thinking something along the lines of what I wrote here. The manga ending's reason for Ryuk killing Light is basically this, while the anime ending's reason seems to be that Ryuk was always planning to kill Light the moment Light was caught, which gives a much different flavor to their relationship.
I theorized that Ryuk had probably loaded up on enough lifespan to see him to the end of his adventure before he dropped his death note in the human world. The reason I theorized this is because we never see Ryuk kill anyone for sustenance. He only kills once in the series, right at the end, and he doesn't seem to need the lifespan then.
Ryuk seems to be very careful in his plan, for example enacting it while he has a second notebook and could therefore make sure that he can't become trapped without a way out, like what happened to Sidoh. Stocking up on enough lifespan would seem to be consistent with this careful planning.