Duet

 is the twenty-eighth album released by Seifuku Koujo Iinkai.

While it is credited to the group as a whole, it is actually an album released by their sub-unit, THE DUET, formed of Hashimoto Mika and Mitsuo Mafuyu.

Disc 1

 * 1) Kuroi Hitomi
 * 2) Hoshi no Fune (星の船; Starship)
 * 3) Motto Motto (もっと　もっと; More, more)
 * 4) Shiroi Iroha Koibito no Iro (白い色は恋人の色; White is my lover's colour)
 * 5) Koi no Vacance (恋のバカンス; Love Vacation)
 * 6) Chiisana Watashi (小さな私; Little me)
 * 7) Maraca (マラッカ)
 * 8) Ohakamairi (お墓参り;Visiting graves)
 * 9) Konoyo de Ichiban Kireina Mono (この世で一番キレイなもの; The most beautiful thing in the world)
 * 10) Sayonara~ Koi (さよなら～恋; Goodbye Love) (A-YA Version)
 * 11) Kuroi Hitomi (Karaoke)

Disc 2

 * 1) Seitansei no Uta
 * 2) Mada Minu Sekai wo Shinjite
 * 3) Gimon
 * 4) Namida ga Tomaranai
 * 5) Ii Hi Tabidachi (いい日旅立ち; A Good Day's Journey)
 * 6) Ameagari no Keshiki (雨上がりの景色; The view after the rain)
 * 7) Yamae Noborou (山へ登ろう; Let's go up the mountain)
 * 8) Ohakamairi ～BIG SKY (お墓参り～BIG SKY; Visiting graves - BIG SKY)
 * 9) Hoshi no Fune (Karaoke)
 * 10) Motto Motto (Karaoke)
 * 11) Seitansei no Uta (Karaoke)

Featured Members

 * Hashimoto Mika
 * Mitsuo Mafuyu