Glyph poacher
From Gnomon Chronicles

Glyph poachers often use Venn diagrams to lure and capture glyphs (nonfiction). In this example, captive glyphs have been separated according to language and lettercase.
A glyph poacher is a game poacher (nonfiction) who poaches glyphs (nonfiction).
Glyph Wardens are the sworn enemy of glyph poachers.