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Tear Jerker: Story Of The Century
Earlier on L makes an offhand remark that he never had family to talk to, only because Erin asked. This bothers her for the majority of the story and the answers she gets from Watari (however vague) don't make her feel any better. This is worsened when she hears that he has no friends to talk to, either.
Erin: So...you're all he has?
Watari: That may well be the case.
This is made even sadder considering what happens to him later...
"Shut up!" barked Misa, her purple fingernails scraping across my scalp like claws as she gripped my hair in her fist and forced me all the way down until I practically had my face pressed against the cold floor, like she were trying to crush me for my blasphemy. I could almost hear my spine cracking, the farther I sank. "Don't you dare fucking compare me to that bastard! You're wrong! We're different. I swear, we're different! We kill for the greater good, not for our gross addictions. The ones we kill...they gave up the right to live the minute they chose to do evil. So maybe everyone is scared of us! But if that's what it takes, then let them be scared! Maybe they all deserve it!"
She spat, "And Light's hair smells wonderful. You just have no taste."
This couldn't be Misa. No way. The Misa I knew was not an angry girl; she wouldn't hurt me like this. She'd almost never cursed, the whole time we'd known each other, unlike me. She'd scold me about cursing. Her profanity was like a long needle piercing one eardrum and exiting my head through the other.
"Misa, please! You must know on some level that what you're doing is wrong. I heard you call Light out on writing his dad's name," I half-pleaded, half-snarled. "How d'you expla—"
The exchange between Soichiro and Light is particularly hard to watch as well, when you consider everything the man went through for Light's sake up until this point, none of which Light expresses appreciation for in the least.
Mr. Yagami heaved Light's name as if it were a cord wrapped around his neck, tightening with every second he gave us no response. A victim, his own kid, dead in his arms, and he could do nothing for him.
Soichiro: Did I really make you do this...? Light...how could you? How could you...you little bastard?
Erin finding out about L's "plan" to test the notebook, after piecing together what Light was planning to have Rem do. She finds him out in the rain in a scene vaguely resembling the one in the anime; when she tries to talk him out of it, he won't listen (though not for the same reasons she initially believes). Panicked, she runs off to destroy the notebooks herself, only to have L chase her into the elevator, whereupon he knocks her out, despite the fight she puts up.
Oh, Watari. I never meant to treat you like that. But I did, anyway. I'm so sorry. I'm sorry for all the times I called you "Grampa" and "old man." I'm sorry for how you were always so patient with me, and I didn't return the favor. I'm sorry. I'm sorry. I'm sorry…
But it didn't matter how many times I said it. Watari was gone. He couldn't hear me, no matter how much I wanted him to. He was gone. Nothing I could do would change that. He was gone.