Originally Posted by
Ryllharu
Just curious, why do you feel the title has to pertain to the story?
Bleach (well, I guess Ichigo's hair), Trigun, Honey and Clover, Pani Poni Dash, Utawarerumono, Higurashi no Naku Koro ni, etc, many titles don't have an overt or direct connection to their contents.
'Silpelit' is also the name of a character of an opera by the author of the Elfenlied song, Eduard Mörike, also mentioned in that song itself. References to him appear only in the manga. In the anime, it's what the Director calls the infertile members of Lucy's kind.