The plot of Saya no Uta tells the story of a young guy named Fuminori. Like all people, he led a normal life, until in a moment his whole world was destroyed, when he and his parents were in a terrible car accident. Fuminori's parents die, and he survives only thanks to innovative medical technologies. As a result of a brain injury, the guy developed an inexplicable distortion of the perception of the world around him: the familiar reality turned into hell. Absolutely everything around is perceived as terrible piles of rotting meat, and his loving friends and other normal people seem like nightmarish, disgusting monsters. Everything that was expensive in this life became a stranger ... the world around us became an unbearable place. Fuminori is trying to live on, fencing himself off from the world and hiding his illness from those around him with all his might, but this heavy burden is gradually destroying his soul. Thinking about suicide in the hospital, he suddenly meets a beautiful girl named Saya, who is looking for her father. Saya, for some strange reason, does not see Fuminori as a monster, and they very quickly enter into close relationships that will change their lives in the most incredible way ...