feline_lump said:
Not being a reader of the manga I've only ever heard of her as "Lucy", and it appears that she isn't called by her original name for much of the story (spoiler?). Kaede is also a very common name that shouldn't be used as a tag without a qualifier.
It's true that Kaede a very common name, good point. Come to think of it, Lucy is a very common name too, so if we settled for "Lucy" maybe it should be lucy_(elfen_lied) (not just lucy as it currently is).
I'll say my humble opinion now. Other people don't have to agree with me, this is just what I think.
I'd rather use the manga as the main source of Elfen Lied information, not the anime.
A few spoilers below:
The manga is the original work. The anime basically only adapts the first half the story of the manga. In my opinion, it seems reasonable to think that the manga is the "true" story.
The anime basically copies the manga scene by scene, but even some of the scenes that made it to the anime tend to be shorter and simpler. Some characters don't exist in the anime (poor Nozomi, Anna etc.) or their characterization or backstory sometimes seems to be lacking in comparison with the manga.
I happen to have a bit of a negative opinion about the anime as an adaptation of the manga.
Kaede's name is revealed only at the end of the story. This seems much like Atem from Yu-Gi-Oh!, whose real name is revealed late in the story. We have the tag "Atem" using his real name.
However at the beginning of the story of Elfen Lied, people from the institution that holds Kaede admit they only call her "Lucy" because they don't know her real name.
I would be OK with kaede_(elfen_lied). We already have a few tags with that qualifier like nana_(elfen_lied) and mayu_(elfen_lied).
In fact, I originally typed kaede_(elfen_lied) for this request, but then quickly edited it to kaede once I realized the latter is currently unused. That said, I realize you're right that the tag should have a qualifier after all.