Lilium plays in four versions in the anime: the opening version, the Griffin Chorus version, the music box version, and the full version found in the 13th episode.

There are other versions and arrangements as well.

In the anime, the song is played by Kouta's music box. Since Nozomi never appears in the anime, Lucy/Nyu never learns the song, Elfenlied. Years later, when she is using her powers to kill some attacking soldiers, she hums this theme, which is among the things that trigger the return of his memories concerning the trauma she caused him out of a jealousy-induced misunderstanding. In the anime, Kouta and Lucy first meet as young children, and he shows her a music box that plays this theme, which fascinates her. He used the idea for another anime later again. Kanbe is also known for his personal liking for Gustav Klimt. Why in latin? - reply message from Kayo Konishi. So she wanted to make the opening theme 'Lilium' like a contemporary Gregorian hymn. While she studied at a mission school, she sang hymns in Latin, and she liked the sounds that the language had.

Kayo Konishi explains the reason why MOKA wanted Latin verses as follows. The anime director Mamoru Kanbe made a single request to MOKA that the opening theme should be a religious music and this was the background why MOKA chose the lyrics from the Biblical texts etc. They jointly arranged the lyrics and composed it. Kumiko Noma performs the opening and a full version as well. MOKA is a two-person musician group that composed Lilium and consists of Yukio Kondo and Kayo Konishi. With lyrics based on the Biblical passages in the Psalms (36:30), and the Epistle of James (1:12) from the Latin Vulgate, and the Renaissance hymn, 'Ave Mundi Spes Maria,' sung in Latin, Lilium is a dominant part of Elfen Lied.

Elfen lied everyone piano