CD-1 "Still's Anti-Climax Sound Group +4" is a recording of the unit "Still" by Koichiro Watanabe (violin, electronics, etc.) and Yoshinori Hotta (guitar, etc.), edited by Koichiro Watanabe himself. (M1 features Keiko Nakatsuka on vocals, and M2 features two songs by the "Tearful Ramen Quartet Koenji Branch" featuring Koichiro Watanabe on drums, Akira Ichiguchi on keyboards, and GESO on guitar, as well as a live recording from 1982 featuring Kimiko Suyama on vocals in the group renamed "Himago" ("extraordinary staircase" + "mada" + "fifth" row).
CD-2 "Garage Session 1977" is one of the many original cassette tapes left behind by Koichiro Watanabe. From M9 onwards, "Yanyan Yanyan no Tsubari 80~81" was recorded on a leftover part of this tape, which seems to be a multiple recording by Koichiro Watanabe himself.