Tsuribaka Nisshi. The fourth single from the album, "Full Jump" was released to a success, peaking at number three on the Oricon chart and certificated Gold by RIAJ. Aiuchi embarked on the concert tour Rina Aiuchi Live Tour 2003 "A.I.R." in November 2003, however, she struggled with aphonia of uncertain cause during the show at Nakano Sun Plaza in Nakano, Tokyo. In December 2003, Aiuchi's first compilation album Single Collection was released. The album reached number eight in Japan and later certificated Gold by RIAJ. On 31 December 2003, Aiuchi achieved a first appearance on Kōhaku Uta Gassen with "Full Jump". The lead single from her fourth album, "Dream×Dream" was released in April 2004. The song served as the theme song to the Japanese animated movie Detective Conan: Magician of the Silver Sky and peaked at number sixth on the Oricon chart. Her fourth album Playgirl was released in December 2004. The R&B-influenced J-pop album peaked at number seven and managed to sell 100,000 copies in Japan. The album has yielded three singles: "Dream×Dream", "Start", and "Boom-Boom-Boom". 2005–2008: Delight and Trip In May 2005, "Akaku Atsui Kodō" was released as the lead single from Aiuchi's fifth studio album. The song served as the theme song to the Japanese Tokusatsu series Ultraman Nexus and reached number seven on the Oricon chart. The double-A side single "Glorious"/"Precious Place" was released in March 2006 as the third single from the album. Both songs served the theme song to the PlayStation role-playing video game Another Century's Episode 2. The single was a success, peaking at number five and sold over 26,000 copies in Japan. Her fifth album Delight was released in May 2006. The dance music-tasted J-pop album was received well by her fans and reached number four in Japan. In support of the album, Aiuchi embarked on the concert tour Rina Aiuchi Live Tour 2006 "Delight" from 8 June 2006. In June 2006, Aiuchi released a collaboration single with U-ka Saegusa, "100 mono Tobira", under the name of Rina Aiuchi and U-ka Saegusa. The song was written for the Japanese television animated series Case Closed and sold approximately 30,000 copies in Japan. In addition to her work for Delight, Aiuchi appeared on the track "Ai Epilogue" on Tsunku's album Type 2. In April 2007, the second single as Rina Aiuchi and U-ka Saegusa, "Nanatsu no Umi wo Wataru Kaze no yō ni" was