As the Head of the Order of books, the Grandmaster organizes and passes laws onto librarians. Often called Head Librarians, they command the highest of respects.

These rare villagers are identified by the red trim and diamonds of their sashes. Their tome hats are larger. Their glasses are more transparent. And you may find a higher level of enchantments from them.

If you ever find one, do drop an Emerald or two. You might find a rare book from them.

Base villager skin by itsamedude:
https://www.minecraftskins.com/profile/5256615/itsamedude

And base Librarian skin:
https://www.planetminecraft.com/skin/villager-4998845/
by thegreatgreenstar
https://www.planetminecraft.com/member/thegreatgreenstar/