Elfen Lied is based on Lynn Okamoto's seinen manga series of the same name and premiered while the manga was still in publication. The anime follows the source material through the first 7 volumes, with several alterations to the story, and concludes with an exclusive ending. In an interview, director Mamoru Kanbe expressed his disappointment in having to 'condense' to story into 13 episodes and felt that more were needed to include significant plot details that would have made the series more emotive.
The artistic design of both the opening and ending sequences are heavily inspired by the works of Austrian symbolist painter Gustav Klimt. Colors and patterns resembling Klimt's distinct style were used and characters of the series were drawn to recreate several paintings from the artist’s golden period, including The Kiss (Lovers). The opening theme Lilium, which is sung in Ecclesiastical Latin, uses lyrics taken from The Bible, the Renaissance hymn Ave mundi spes Maria, as well as the alchemical compendium Theatrum Chemicum.