Naoshi Arakawa’s Your Lie in April has significantly left a mark on the anime and manga world with its heartrending story that still retains a huge fan following after all these years. With Kaori Miyazono’s life hanging in the balance, Kosei Kousei's appearance for the performance wasn’t expected.
However, given his devotion to music and his profound respect for Kaori, he delivered the performance of a lifetime. Kaori Miyazono’s death left an indelible mark, subsequently creating an inevitable void in the finale that evoked nothing but tears from fans, who deeply felt bad for Kousei.
Nevertheless, the series somehow failed to explain Kaori’s illness in depth, resulting in most fans presuming it to be just cancer. However, in reality, Kaori battled a distinctive and life-threatening disorder that gradually consumed the majority of her existence.
Disclaimer: This article contains major anime and manga spoilers from Naoshi Arakawa’s You Lie in April.
Your Lie in April: Kaori died of a rare genetic disorder
Despite her free-spirited and lively front, Kaori Miyazono of Your Lie in April led a very difficult life battling a rare genetic disorder called Friedreich’s Ataraxia (FRDA or FA) that affects about one in every 50,000 people.
Although it is never revealed neither in the manga or anime, Kaori inherited the degenerative disease from both her parents, each carrying one copy of the defective FXN gene, which ultimately affected her.
Friedreich’s Ataraxia typically begins between the ages of 5 and 15, though it can also manifest later in life. Kaori left behind a letter that was meant for Kousei, in which she explained everything about how she first stumbled upon him when they were just kids, finding her passion in music once again, and the lie about having affection for Ryouta Watari.
In her letter, it was revealed that she had gone through surgery when she was just a child and then got treated regularly as an outpatient. However, things worsened when she collapsed in her first year of junior high, around the age of 12-13. This was the very moment when Kaori’s parents discovered that their daughter’s health started deteriorating.
When Kousei met Kaori for the last time in the hospital, he couldn’t help but notice an obvious change in her appearance. Her skin was paler than before, and she looked like she had lost even more weight.
Additionally, Kaori wasn’t even able to stand on her own, as her disorder had damaged the peripheral nerves in her legs, and it was discernible that she also lost sensation due to the nerve injury. Unfortunately, Kaori couldn’t survive the surgery, and she sadly passed away on the 18th of February at the age of 15.
What happened to Kousei after Kaori died in Your Lie in April?
The weight of Kaori’s passing was unbearable for Kousei. However, in the end, it was a cathartic and transformative moment, where losing her led to a profound emotional change, giving him a sense of freedom from his pain and misery.
Although Kousei had already started growing out of his shell, the moment he encountered Kaori, the memories and tranquility she left behind helped him live life to the fullest.
After reading Kaori’s letter, Kousei discovers that her affection for Watari is just an act to get closer to him. Kaori knew that Tsubaki had feelings for Kousei, which is why she never befriended him in a straightforward manner, as she didn’t want to hurt her feelings.
After Kaori’s death, Kousei decided to live happily to honor her soul and never got depressed over things that weren’t in his control. Kaori served as the beacon that guided Arima out of his darkest moments into the light. He continued practicing piano and held onto Kaori’s last words of her letter, which was to never forget about her existence.
Did Kousei end up with Tsubaki in Your Lie in April?
Your Lie in April anime and manga end with Kousei stumbling upon Tsubaki on his way home from school. Prior to this encounter, Tsubaki wasn’t courageous enough to confront her true feelings for Arima. However, Kashiwagi knocked some sense into her by making her follow her heart rather than her brain.
Kashiwagi made Tsubaki realize that this was when Arima needed her the most. Upon meeting Arima, Tsubaki kicked his shin and expressed her feelings by telling him that she wouldn’t like him to live all alone.
She further exclaimed to live with him forever like a guardian angel. Ever since they became close friends in childhood, Tsubaki referred to Kousei as her “kid brother.” However, things changed over time when she realized that she had feelings for him.
If it weren’t for Kaori’s letter, Arima wouldn’t have known about how Tsubaki felt towards him. While the author of Your Lie in April hasn't officially confirmed Kousei's romantic partner, many fans strongly believe that Tsubaki was the one he ended up with.