X/1999, Volume 18: Inversion By (author): "CLAMP"Genres:Fantasy books Comics books Graphic Novels books Manga books Supernatural books Shojo books ISBN1591167825ISBN139781591167822AsinX/1999, Volume 18: InversionOriginal titleX (????) (X/1999) 18SeriesX/1999 #18The balance of power is shifting as the Seven Seals with the power to protect Earth face the Seven Harbingers who are fated to destroy it. Rated for older teens.