Yōsei Teikoku (妖精帝國, lit. "Fairy Empire") is a five-member Japanese musical unit, formed in 1997 and part of Team Fairithm. Yōsei Teikoku attempts to revive the Request Empire that exists between the human world and spiritual realm --known as "Spiritual"-- through their music. The purpose of their music is "to make humans remember the pure heart inside them that believes in fairies, forgotten before we knew it". "Gothic" and "empire" are key words in their musical ideas.