DEF.DIVA was created as a special unit in late 2005, following a series of special units formed at the end of the year that included Gomattou and Nochiura Natsumi. The name stands for "definitive diva". Their debut single, "Suki Sugite Baka Mitai", reached #1 on the Oricon charts and, at the time, held the record for the lowest-selling #1 single in Oricon history. (The record was broken by AAA's "MIRAGE" in 2008.) DEF.DIVA performed at the 56th Kouhaku Uta Gassen at the end of the year. They sang the official 2006 cheer song for the Touhoku Rakuten Golden Eagles. The group has been inactive after 2006.
- [2005.10.19] Suki Sugite Baka Mitai (好きすぎて バカみたい)
- [2006.03.25] LET'S GO Rakuten Eagles (LET'S GO 楽天イーグルス) (Indies)
Compilations / Other
- [2005.12.21] Hello! Project - Petit Best 6 (#1 Suki Sugite Baka Mitai)
- [2006.12.20] Hello! Project - Petit Best 7 (#16 LET'S GO Rakuten Eagles, #17 Ready Go! - Morning Musume, DEF.DIVA, Berryz Kobo)
- [2008.12.10] Hello! Project - Hello! Project Special Unit Mega Best (#10 Suki Sugite Baka Mitai)