Sonoko Kawahara, known as Sonoko, is a Japanese singer-songwriter and pianist. She gained popularity in the 1990s with her soft and dreamy pop sound, characterized by her sweet and delicate voice. Her debut album "In Heaven" was released in 1999 and was followed by several other albums over the years. Sonoko's music has been described as ethereal and melancholic, and she often collaborates with other artists in various genres such as electronic and jazz. Her music continues to captivate audiences in Japan and around the world.