A charm is another word for a rune, enchantment, or method of creating magic item. The Charm of Vanity interacts with the Appearance/Charisma score of the item weilder
Even though I often didn't see my father for months at a time, I know he loved me as much as I love you, Son, and as he once said to me, 'I may not be the best father, but I will always send my prayers when you need them the most,' and that is what I intend to do for you. Remember this, even if you don't see me for a while and want to hate me, I love you.
THE GNOMES OF UDNALOR: Part I
Upon entering the deep underrealm of Udnalor, one must first pass through the upper halls, which were the residences of the gnomes in days of past glories. Now they have abandoned the fading tapestries to the worms and moles, and an uncanny silence reigns, laid over the oaken tables like the thick layers of dust and humus.
There may be creatures which now inhabit these areas: nests livid with giant maggots, rats and other vermin.
The watchtowers and passageways which lead to the Overground are frequently trodden, however. After all it takes a great many small humanoids to hoist a single giant rabbit corpse back through the fathoms of earth.
The gnomes primarily hunt giant rabbits with bows and arrows tipped with the subterranean poisons concocted by their best alchemists.