The classic "Sorrow" is the part in episode 19 where he dies in vain and snow falls in the sky. It is very sad. Then the part when Sasuke ran away and chased Sasuke, and then Neji fell, seemed to be called Neji's death. The original TV anime's part about Sister Guren, a very lonely flute, is called "Guren" in the OST. I like this song very much. When Naruto was alone, the lonely harmonica song "Loneliness" often appeared. "May Rain", Payne's appearance music is quite tragic, I don't know what it is called.