"W-B-X " is the eleventh single by Japanese singer-songwriter Aya Kamiki and the first as a collaboration with TAKUYA, former guitarist of the Judy and Mary, as Aya Kamiki w TAKUYA . The song is Kamiki's first release under the Avex Trax label and is used as the opening theme for Kamen Rider W. It is also a single from her first album released under Avex titled Individual Emotion.