Ratu was an Indonesian music duo formed in 1999. Ratu entered the Indonesian musical scene with their first album, Bersama (Together; 2003). In 2004, the group formed anew with Mulan Kwok as vocalist. This new line-up proved more successful, with their most successful songs – "Teman Tapi Mesra" ("Friends with Benefits") and "Lelaki Buaya Darat" ("Womaniser") – released in this period; both song titles later became common terms in the Indonesian vocabulary. The group's second studio album, No. Satu (Number One; 2006), sold 200,000 copies on the day of its release, a record for an album by an Indonesian female group. The group dissolved in 2007. Ratu was the most successful female Indonesian music group of the 2000s.
Ratu entered Indonesian music industry in 1999 with Maia Estianty on instruments and Pinkan Mambo on vocals. They inevitably had to take a short break after Mambo's departure in 2004, then the group formed anew with Mulan Kwok as vocalist. No one knew the members change brought more success with their hits "Teman Tapi Mesra" ("Friends with Benefits") and "Lelaki Buaya Darat" ("Womaniser"). This powerful duo also became the first musical act who got "Artist of the Year" and "Group/Duo Artist of The Year" at the MTV Ampuh music awards.