"Embryo" (stylized embryo) is a single released by Dir En Grey on December 19, 2001. The single edit of "Embryo" features lyrics entirely different from those on the album: while the single version speaks of the filth of society and the wish to rejoin a deceased mother, the album version depicts an overtly explicit scenario of the protagonist being raped by its father and carrying his child while Mother looks on from Heaven. This is the first Dir En Grey song in which bassist Toshiya has ever played with finger picking technique.