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Tear Jerker: Hell Girl
Hell Girl shows us many sad situations, but the end of the 2nd season takes the crown; the last episodes are a real avalanche of Tear Jerkers.
First Season Episode 17, features an Ill Girl named Nina, who was abandoned to die in a sanatorium. Her memories and her desperate longing for her father who never came back for her turned her doll into a youkai, who, even after her master's death, continues to wait for her "father"'s return. In the end, Ai helps the doll discover the truth, and as her memories return and her illusions fade, the doll disintegrates in Tsugumi's arms.
And then there is the very subtle instance at the end of the third season. One hopes that somehow, somehow, Tsugumi learns Fate can indeed be denied and that Yuzuki was, in the end, saved ... otherwise her walking away, her last shreds of hope in this bittersweet world finally battered into the dirt and ground away is heartbreaking.
A minor example, but damn did the show hammer home the "pets are family too" theme in episode 4 of the first season. Watching a dog die on camera right off the bat is hard, but then comes the Happier Times Montage...
Even sadder is at the very end of the episode when Junko, the dog's owner, prays to her family and basically tells them not to wait up for her in Heaven . . .
Hone-Onna's backstory, and just about everything about the episode where it's revealed.
Episode 13 of Futakomori ends with one. The man who contracted them was a serial killer who wanted revenge on some guys who just wanted to appear on camera when TV crews were reporting on the accident that resulted on the death of his wife and son, and his daughter entering a coma. Pretty petty, huh? But wait for it. He still has hopes that his daughter will awaken someday (she's been in the coma for five years), but having contracted the Hell Correspondence to take out the last guy, he was resigned to go to hell and atone for his sins. But the catch is: when you go to hell due to using Hell Correspondence, the only thing that grants you access there is having sent your foe there. And nothing else. The murders he committed will be paid another way. And this way is: he's going to jail, with what little life is lhe has left, just as his daughter is awakening from her coma. So, even if he lives longer than his cancer would let him, he'll never see his daughter again. What the old man did is indelible, but still, damn did it touch some heart strings.
Mitsuganae Ep 25, Yuzuki's life, the entire thing.
Episode 11 of Futakomori . A woman wants to adopt a stray cat that's been hanging around her apartment, but a reclusive neighbor begins harassing her, telling her to leave the cat alone. When the harassment becomes too much to bear, (and, after thinking that the neighbor has killed the now-missing cat) the woman sends her neighbor to hell. It's only after entering the reclusive neighbor's apartment that she discovers the cat alive and well and the walls covered with cat photos. The neighbor actually loved the cat, but was too shy to tell the woman that the cat belonged to her. The sadness of this episode comes from realizing that a pet could mean so much to a miserable lonely human being, and that the misunderstanding which ultimately led to two people being sent to Hell, could have probably been cleared up if only the reclusive neighbor had spoken up about owning the cat, instead of turning to threats and harassment.
Episode 17 of Futakomori is one of the saddest episodes of the season. A little girl named Nene contracted Ai to send her mother Honami to Hell because she believes, along with her paternal grandmother, that her mother killed her father. When Nene walks in on Honami in a confrontation with the grandmother in which harsh words about her father are exchanged, Nene runs to a bridge with Honami in pursuit. When Nene takes out the doll and threatens to pull the string and send her mother to Hell, Honami reveals that eleven years ago, she sent her husband to Hell to put an end to the violence and abuse he visited upon them both. She shows her daughter the black fire mark that all contractors with Ai receive when they've sent someone to Hell and then begs Nene not to pull the string — Honami is already going to Hell, but she doesn't want her daughter to share her fate. And then, to keep Nene from damning herself by pulling the string (and despite Ren's best efforts to save her), Honami throws herself off the bridge and into the streets below, meeting her fate with open arms.
Episode 18 of season 1 is just devastating. A friendless, lonely girl's beloved Welsh Corgies bite a bitter, evil, and very paranoid old woman who proceeds to enslave the girl and holds the dogs hostage; she threatens to kill them if the girl doesn't do what she says. After the hag kills one of her dogs, the girl contacts Hell Correspondence. However, she hesitates, and she is rewarded by having the old woman kill her other dog. It gets even worse. The second dog had just recently given birth. And yes, the puppies are all killed too. That's right, the girl loses her only two friends and any chance of saving their babies, all because she's hesitant to pull the string. She finally does so... after the woman is arrested for the murder of her parents and infant son, whom she killed to avoid having to share her vast fortune.
The end of the Season 1 finale is part Tear-Jerker, part Heartwarming. To sum up: Tsugumi refuses to send Hajime to hell, despite Ai's attempts to manipulate her with twisted memories of her mother's death. She then proceeds to tell Hajime how happy she was to be with him and go places and do things together, like eating dinner or even watching TV - how she's happy just to have him, even though her mother is gone.
"I miss Mommy. I'll always miss her. But Hajime...Daddy...I'm okay because I have you."
This exchange becomes even more of a Tear Jerker come Season 3, where we learn from the now-adult Tsugumi that she and her father have drifted apart and lost touch, and that he basically became tired of trying to convince people not to condemn themselves to Hell.
When Hone-Onna goes to the girl in season 2 episode 16 to find her dying from being stabbed by the woman who used her. You see a small glimpse into Hone-Onna's back story as she helps the girl enter the woman's name into Hell Correspondence. After the revenge is acted out, she returns to find the girl dead. Hone-Onna gently closes the girl's eyes, telling Wanyuudo and Ren to leave her alone.
Episode 23 of Season 1 is particularly infamous among fans for its ending. The kindly young nurse is sent to hell by some random drug addict on the street, who she'd never seen in her life, and who did it just because he could. Even Ai's assistants are shaken by this.
Episode 12 of Season one begins with a hikikomori called Sawai Akane, who wants to send her teacher to Hell because he keps on trying to get her to go back to school instead of understanding her like her online chat-friend. She eventually does go back to school, though her classmates are whispering behind her back that she should have stayed home, and even writes a happy message to her net-friend... who turns out to be the teacher. He didn't know who she was, and fortunately she believes him and they make up. She admits to the teacher that she wrote his name into the Hell Correspondence, and he says he actually WANTS to go to Hell, because his life is so boring and mundane and he can't put up with it anymore. She is hesitant, but eventually, she does do it. On the way to Hell, Enma Ai gives the teacher a What the Hell, Hero?, explaining what'll happen to Akane just because of the teacher's ennui and selfishness. He of course repents and Akane can be heard asking the teacher to wait for her down there. (To add another layer of tragic, their meeting is unlikely, because Hell IS a vast place after all, as Ai herself said a couple of episodes previously.) After the teacher is taken to Hell, Ai asks her grandmother if it's all right for someone to actually wish to go to Hell like it was Heaven...