妖精帝國 (Yōsei Teikoku, sometimes Das Feenreich, literally Fairy Empire) are a five member Japanese band. Part of Team Fairithm, the band previously consisted of just vocalist and lyricist Yui with guitarist and composer Takaha Tachibana. The band has since included bass player Nanami, drummer Gight, and lead guitarist Shiren to their line up. The group have been active since 1996 and have done their rounds around the doujinshi/indies music circuit.