Yes, "flutterby" does make sense. Unfortunately, English doesn't work that way.
You could make it happen, however. For years people were told there's no such word as "conversate". I understand that it's now in the dictionary. A two syllable word (converse) is now being replaced with a three syllable word (sensible or senseless?) So if you use flutterby frequently enough and teach others to do the same, you never know.
PS. I see that spell check still doesn't like conversate.
