Seika Iwashita (岩下清香) was born in Osaka, Japan. She grew up in Kagoshima and later moved to Tokyo. She used to belong to a punk band called "LOTUS ", until the producer thought that she should have some other singing jobs. It was at this time that Seika joined "5th GARDEN " as a recurring vocalist, and a bit later as a vocalist for composer Yoko Kanno and the groups "Comoestas " and "The Nano Watts ". Seika is currently with "Rose-Unlimited " as the vocalist with co-member Takashi Yoshida ,

She has released 2 solo albums, sung for several CMs, and is an uncredited back-up vocalist for several of Japan's pop stars. She is most known for her unique jazz-toned and pure-sounding voice, attaining to her popularity in the nightscene, particularly in night clubs in Shibuya and Aoyama where she can be seen performing live.