- Yokoku (予告; Announcement)
- Catalog Number
- Yokoku (予告)
- Machigai Sagashi (間違い探し; Spot the Difference)
- Tsuki ga Tokeru (月が溶ける; The Moon Melts)
- Yokoku (instrumental)
"Yokoku" is the 37th single released by aiko. The first press edition comes with a color tray and 8-page booklet.