Lilium is best known as the opening theme of the anime Elfen Lied, which aired in 2004. Credited to Konishi Kayo and Kondoo Yukio, the opening version became memorable for its choral arrangement and stark contrast with the series' violent, tragic story. Over time, it spread through anime fan videos, AMVs and character edits, where creators used it to signal sorrow, psychological horror or a serious emotional turn. It remains a recognizable track because even short excerpts immediately evoke the show's bleak tone.