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Tear Jerker: Death Note
Episodes 1- 20
Raye Penber uses the Death Note unknowingly when Light holds him hostage and forces him to write down the names of the FBI agents investigating Kira. Penber's allies die by his own hand. Made even worse by the fact that Penber cannot go to Heaven nor Hell now that he has been forced to use the Death Note.
The death of Naomi Misora. She comes so close to bringing Raye's killer to justice, and this is what ends up being the death of her. The small, metaphorical scene with the noose, the music... so sad.
The fact that Light actually revealed to her that he was Kira makes it even sadder. If you think about it, she's basically destined to commit suicide, but for the last moments of her life, she has to live with the fact that she just gave her fiancé's killer all the information she had, trusted him and let him kill her without her knowledge. And now she knows who killed her fiancé, but she can't do anything about it because of the Death Note.
Gelus is just so sad-looking and his death to save Misa's life was pretty heartwrenching. Especially for poor Rem who was couldn't do anything but watch.
Especially since it was basically one Stalker with a Crush sacrificing himself to save the object of his crush from another Stalker.
There's also Misa Amane's strongest scene. She's in restraints, begging Rem to kill her, and even tries to bite her own tongue off. Of course, she doesn't succeed, but it was a real turning point for her character. Well, it seemed so at the time...
The first scene we see of Aizawa after he leaves the task force. He's sitting alone in a park and his family turns up he breaks down crying because he missed out on so much of his daughter's life made worse with her coy confusion and the questions "What's wrong dad? Mommy, why is daddy crying?"
There is the possibly more heartbreaking alternative reaction that he's not crying because he's missed out on being with his family, but rather out of shame that he believes himself to have been the weak link in the task force and was not strong enough to stick out the hunt for Kira with his respected friends and peers, guilty that he gets to enjoy a normal family life again while his comrades have to continue their mission without him.
The moment when Misa made the deal for the Shinigami eyes for the second time.
Also consider that his notebook was given to Misa by Rem, as she believed it belonged to her, given that Gelus died to save her with it. And then after that, Light gets a hold of it, uses Misa, gives the notebook away to some evil bastard called Mikami and it ends up getting burned by Near. Especially sad when you consider Rem's line of the notebook being the only reminder of Gelus' existence and the scene in which Rem tells Misa that the notebook belongs to her and she clutches it to her chest. Try not to wish that Light and Misa had never met after looking over that scene again.
Light regains his memories. What's the first thing he says? "Exactly as planned.", indicating that he was behind it all along. From that pointon, the innocent and pure Light Yagami was no more, replaced by the homicidal killing machine he has become.
It's the fucking scream. It isn't just Light getting his memories back. It's the innocent, cheerful boy he's become over the last few episodes, watching and reacting in horror as he realizes that he's Kira - the very person he swore to hunt down - knowing that he's going to "die" and that the monster he truly is, is going to reassert himself, and it will be as if the idealist - the Light he could have been if he hadn't found that fucking book or if he'd gotten over his boredom - never existed.
L calling Light his only friend, moments before his death.
This one appears to have been undone by Word of God. How To Read 13 says L has no friends at all and that it was just a lie he told Light, even though he knew he'd hardly believe it. Whether you take that as a Fanon Discontinuity is up to you.
The How To Read profiles were listed somewhat like interviews, meaning some of the definitions were altered somewhat to match the characters. So Light being L's only friend was true, and L was lying, to the audience and himself, so that he wouldn't grow attached to his only true friend. This only makes L's death and confirmation that Light was responsible for it all the more heart wrenching.
One of the most heart-wrenching moments of the entire series, of course, was the deaths of L and Watari at the coerced hands of Rem, who, because of the rules of the Shinigami, was also killed in the process.
And don't forget L died failing to bring down Kira. However, the Movie's version of this where L prevents himself from being killed by Rem by writing his own name into the note, but adding that he would die 23 days later. Sadly Watari and Rem don't make it out alive. And you see a few shots of Rem crumbling into dust. Finally, there is the scene at the end where Light's entire family mourn his death, his father only having told them that he was killed by Kira.
As for L's death, the scene of L's funeral goes from Tear Jerker with Soichiro promising to him that he'd make his death worth it and Matsuda crying, to rage-inducing with Light making up lies about how he'll avenge L's death by killing Kira himself. It quickly turns to terrifying with Light going absolutely berserk with his laugh and screaming at L's grave that he has won. In a deleted scene, he even "humps" it.
L and Watari looking at one another through the computer monitors and L calling Watari's name, first quietly, and then loudly just before Watari cuts the transmission and erases the datbase due to his death. Particularly sad since that episode implied that Watari was the closest thing L had to a father, and the angle and wide-eyed look he has in the monitor Watari looks at makes him look particulalry childlike. It's also the first time L's voice seems to have tender emotion and vulnerability in it.
It's even more depressing since most people are so upset by L's death that they completely forget the fact that Watari died too. L's death wasn't as bad (though still was terribly horrible) since he was actively fighting against Kira and in the end one of those two had to die, but Watari's death wasn't necessary, and that just makes it all the more heartbreaking.
The really simple scene added in episode 25 of the anime where you see Watari bring a child L into Wammy's House for the first time. Not just the way the scene was shot, and the haunting music playing, but the fact that it shows that L was just as human as anyone and how Watari was probably the only person who really cared about him.
The death of Deputy Director Yagami. The saddest part about that was that thanks to Light's relinquishment of the Death Note, the Shinigami-eye-wielding Director saw Light's lifespan, so he died genuinely believing that his son wasn't Kira.
In the manga, Soichiro's last words, beginning with "Light, I'm counting on you to..." are cut off by Light trying to get him to kill Mello with the notebook! Light's panicking is understandable but it's an example of how badly Light's humanity had to suffer.
And the moment in the hospital just after his non-Kira heart attack, when, in full knowledge that Light is a suspect, he quietly explains to him that it isn't Kira himself who's evil, but the power he's using. Utterly tragic - especially since Light, while briefly affected, is a brick wall, and because that distinction between people and their acts is something Light will never grasp.
The shot of Light's mother Sachiko slumped at her table. Her son Light has all but disappeared from her life, her daughter Sayu is confined to a wheelchair and catatonic, and her husband Soichirou has just died trying to stop Kira.
And Soichiro's ashes are on the table in front of her. That's what that neatly wrapped box she's contemplating is.
Also the entirety of the finale of The Last Name, from the emotional punch in the gut when Light and the audience realise that the Death Note didn't work on him, and he saw everything, to the scene when he's walking home with Sayu, who's crying because she thinks Kira killed Light. Just... ouch.
The look of absolute horror and heartbreak on Soichiro's face when Light demands that Ryuk kill them all. Kinda makes one glad we didn't see his reaction when Light wrote his name in the Death Note. It couldn't have been pretty.
Mikami's horribly depressing backstory. Especially when the boy he protected thanks him and adult Mikami says 'as long as I heard that word, it made me want to help them every time'. The contrast between what a sweet kid he was and the way he is now is just so stark.
Worse with Fridge Horror when you realise like L, Mello only had one friend.
Matt's death in general due to the way it is shot, which seems to imply he was meant to be a lot more important character, as he had such a minor role yet there is the lingering shot of his cigarette.
Kiyomi Takada's death. To review: poor Takada had been kidnapped by Mello and killed him, causing Mello to crash the truck. Takada survived, naked, in the back of the truck. She called Light, and was clearly frightened. Light had her just keep killing, while she's in the back of this truck, cold, naked, frightened, and alone, and out of her devotion to him, she trusts him and keeps killing, and what happens? Light makes her burn herself to death.
The moments before Light's death in the anime are particularly sad. Specifically when he's running away from the warehouse and we start seeing flashbacks to the first episode showing him walking along the same road just after finding the Death Note, and he looks so young. It was surprisingly heartbreaking, considering he's, y'know, a sociopath.
Light losing it was bad, Matsuda losing it was horrible. He so genuinely seemed to admire Light, and seeing him shoot him repeatedly with tears streaming down his face (which provides the page image), then having to be stopped from killing Light by the other officers was some seriously upsetting stuff. And of course, Light's reaction to this is tearjerking as well:
Light: Matsuda, you idiot! Who the hell do you think you're shooting at?!
His death in the movie. Dying in his father's arms, still claiming he was justice. The arms of the father he'd tried to murder only minutes before. Oh, Soichiro...
When Light realized that he there was no one left to help him, and him still not realizing it was largely his fault.
This- especially in the anime where he's lying on the ground in the moments after being shot, calling out to Takada and Misa, asking what he should do in a voice like that of a little lost child.
The final music that plays in the anime version during Light Yagami starting to slowly die and when he sees an image of L looking over him.
Misa Amane's last scene in the anime, where she sadly stands atop of a building, dressed up in her Elegant Gothic Lolita garb, eyes closed. This comes with the very strong implication that she committed suicide just moments later. Especially with this incredibly sad music playing in place of the normal heavy-metal ending, the credits rolling over, jerking back and forth between shots of her and Woobie-ified Light... Worst part? How To Read cites her death date as Valentine's Day.
Consider also that this is not the 2nd Kira, Misa in full Cute and Psycho mode that dies, it's an innocent woman who has been jerked around all her life without her knowledge by the power of the Death Note. Rather than the insane, evil Kira persona being the one that died, Misa committed suicide after she'd gotten her life as a normal human back. Even without Light around to use her, she just couldn't win.
There’s some Fridge Horror at work too: consider that she traded half her remaining life twice for Shinigami eyes, and she dies only a year after the main story — that means she would have only had four years left to live even had she not found her own Death Note. The poor girl never had even half a shot at a normal life.
Light's last conversation with Misa in the manga is just ... heartbreaking. Misa is cheerful and glad that she's gotten a chance to talk to Light, telling him happily about the hotel room. And Light is completely "Yeah, good, she's not something I need to worry about at the moment." And he hangs up — if he even bothered to say goodbye to her, the reader doesn't see it. And that's their last. Conversation. Ever. After Misa gave her life and soul to Light, suffered L's torture for him, begged Rem to kill her when she couldn't take it any longer, and let his control dominate her life completely — that was their last conversation. They were engaged to be married, for the love of God; yes, it was only a pretense on Light's part, but they had been together for years, and Misa finally had the family that she had lost when her parents died. And she kills herself after Light dies. AND THAT WAS THEIR LAST CONVERSATION.
At the very end. Near is surrounded by a bunch of toys, doing what he does best... and eating a bar of chocolate.
It's easy to see Light was a good person before getting the Death Note, and genuinely cared about his family and justice. When he gives up his memories of being Kira and reverts to the kind, caring person he used to be, it's so heartbreaking when you realise it was only a scheme, and was never going to last in Episode 24.
In Change the WorLd, the scene where Maki, one the kids L has to protect decides not to kill the villain (who is also her father's murderer) and ends up crying as L holds her and says "You're a good girl. I believed in you." And there's the bit at the end: L takes the other child, a little boy, to Wammy's, and finally give him a name: Near. He then hands him a bag, the newly-named Near looks inside and pulls out the toy robot he had liked in a store. Several moments later, as L leaves, his voice-over reveals that he's not ready to die; he wants to live longer.
That's one of the saddest things about Death Note. Light was so smart and could have done anything he wanted, but when he found the Death Note it basically ruined his life. He was never a bad person when he didn't have the Death Note.
In a sad version of Fridge Horror, the survivors of the Yagami family. And if thinking about it wasn't bad enough, then some really good fanfic writers got ahold of it...Not. Fair. Light ruined the lives of the people he should have loved most in the world and they did nothing wrong. And the bastard STILL didn't realize what he was doing!
...and the manga:
Light (on the phone): Sorry mom, I can't come home again this year. Tell Sayu that I promise I'll find time to come back home next year so we can spend some real family time together.
When he does lose his memories, however, he goes from sinisterly calm to outright desperate. Afterwards, Higuchi continues killing criminals, but L decides to lie to Light and say that no killings have happened. Not only that, he was confined for 50 days straight, he's seen on the ground and by the looks of it, he looks like he was dying of starvation. What makes it worse was when L tricked Light into believing that his father was going to kill him. Right when his father pulled the trigger and the gunshot was heard, it seemed that Light died and his father crossed the Moral Event Horizon for doing this. But then we see that it was a test to see if Light was Kira or not and gun was just a blank.