One thing that Your Lie in April handles remarkably compared to other anime is the concept of dealing with illness. The ill girl is hardly a rare trope in anime—in fact, I’d put it up there with “hit by a car” and “that exact same cicada noise” in terms of things likely to crop up in any randomly selected series. We don’t often see anime that tackle what it’s like to be chronically or terminally ill for the person who is actually ill, though.
The moment that struck me and continues to stay with me in Your Lie in April is at the end of episode 15. Far from the elegant fainting and hospital visits filled with reassurances that represent how Kaori’s illness looks to everyone else, this scene is an honest glimpse into how it feels to her: agonizing, frustrating, outrageously unfair. She’s helpless in the face of it, and, as we see, it’s infuriating.
Too often, a character’s illness is a plot device that is used to catalyze the emotions or behaviors of those around her, while she essentially sits there smiling and bearing it, perhaps nobly hoping that her last wish will be granted. A great example is Clannad: both Fuuko and Nagisa are confined to bed for long stretches of time, prevented from attaining what they want by something out of their control, yet they remain composed. Fuuko’s primary concern is for her sister’s wedding, Nagisa’s that she not be a burden on those around her. We don’t see them as frustrated, angry, or in pain, or even get a glimpse into any internal monologue that might be less than pretty; they’re noble and pitiable figures.
That kind of character can work well with an otherwise strong narrative (Key’s stories remain probably the best example of using this trope effectively), but it nevertheless relies on the idea that meeting any illness up to and including a terminal one with serene acceptance automatically makes the ill person sweet, wise, and noble, or—more to the point—sweeter, wiser, and nobler than anyone who wouldn’t deal with their condition similarly. This is nonsense, and beyond that, lazy writing. I don’t doubt that there are some out there who do come to accept their illness with perfect philosophical composure, but I don’t think it’s common, or easy, or a state of affairs to present without comment. To do so is to rely on the audience having a vague idea that chronic and terminal illness sucks, without actually engaging with the concept or forcing the viewer to confront it. Yes, confronting an uncomfortable concept is difficult to do successfully; on the other hand, only a poor story doesn’t strive to reveal something about the human condition.
Your Lie in April really tries to engage with the idea of terminal illness, even if it doesn’t always get it right. The characterization of Kousei’s mother leans too far in the other direction, to be sure: anxiety over your impending death and your child’s future manifesting as too much pressure on him to succeed, okay; abuse, NOPE, that’s not explicable or justifiable by illness alone. I do appreciate the attempt to show that she’s not mean because she’s a horrible person; she just lacks the necessary coping mechanisms to deal with her fear and frustration in a healthy way, and of course her illness accounts for a huge part of those feelings. That deeper look into her character was too little too late when it finally manifested in the show, though, and there was no character motivation or story reason that made it necessary for her behavior to escalate to straight-up abuse; I agree with those who have said that scenes with Kousei’s mother can be needlessly melodramatic (and distressing to viewers who have suffered abuse and probably don’t need to be seeing it tossed around as a plot device).
Where Your Lie in April fails with Kousei’s mother, though, it succeeds spectacularly with Kaori. Kaori, who begins the story when she chooses to become the person she wants to be, if only briefly, and arranges to meet Kousei. Kaori, who drives the story when she forces Kousei to work through his issues surrounding the piano, and to run into her again and again so that he can’t let go of the feelings he’s not sure he wants to be having. Kaori, who ends the story when she chooses to have a surgery that she doesn’t survive, because she so badly wants that small chance to be able to perform with Kousei again.
Kaori is selfish. She’s selfish because she’s dealing with something that won’t ever get better or go away—when it’s done, there will be nothing left. So she decides to do something, something selfish, about it. She lies. She chooses not to put aside her feelings in favor of Tsubaki’s, even though she knows about them. She isn’t honest with Kousei about her feelings, because she doesn’t know if it would be easier or harder that way. She uses Watari as a not-entirely-ignorant go-between. Still, Kaori is kind. She loves Kousei. She supports him, even when it hurts her to hear him play without her. She tries to do what’s best for him, though she doesn’t always know what that is. Even when it results in her screaming and crying at Kousei from her hospital bed, she’s trying to be kind.
Kaori has the kind of beauty that comes from laughing whenever she’s happy, and crying whenever she’s sad. For someone with so many secrets, she sure wears her heart on her sleeve. She finds joy in small things. She’s also kind of a mess. Her inability to stand and hold her violin frightens, enrages, and crushes her. She always ends up acting out, though she’s trying so hard to stay collected.
Kaori’s agency is intentionally subtle throughout the series as a means of building up to the last episode, despite the completely unsubtle nature of her presence in Kousei’s world. What’s revealed about her life most often denies her agency—performing means the most to her, yet she is denied the chance again and again by her inability to stand and hold her violin—and shows her very real helplessness in face of her illness, while burying the lede tremendously effectively.
Kaori has a dynamic personality, and feelings, and agency—everything that the traditional ill girl lacks. This makes her so much more endearing than an average character, and it’s why finding out that she’s been fighting in the face of her illness to perform with Kousei Arima is so powerful and tragic in the end. Kaori remains a main character even when she’s off-screen for significant chunks of time because the entire story is the tale of her agency, even as it follows Kousei and how he grows as an artist.