Depending on ther origin fae either age significatnly slower than humans, or sometimes not at all.
one of the number 1 rules for encountering fae is to not eat ther food. A lot of Lore suggests that doing so will prevent humans from being able to escape the fae realm. But if a human eats or drinks fae delicacies while outside of the fairy domain, they may find that the food and drink of their own mortal world never satiates the same way again. The Gargoyle initiates members by having them drink the tonic and swallow the seed, but what if rather than these things catalyzing some esoteric process, the simple act of ingestion of alone the process? What if after a single sip of the Tonic you find that anything else, water, wine, whatever, no longer quenches your thirts? That alone may lead you to join the Castle, but coupled with the seed's nullification of food's desireablitity it makes one very susceptible to influence.
Surely a whole sentence is not necessary for this information but since we're already here, "The Gargoyle" is likely not the real name of the Castle's leader. And I would also confidentally assume that "Avery Etidorpha Wormwood" is not their real name either. Obvously there are nefarious (and benign) incentives to conceal one's real name, but for Fae it is a crucial to one's autonomy. There is much power in a name for Fae, knowing someone's name gives you power over them. Members of the Castle never call the Gargoyle anything other than "Gargoyle" or sometimes an affectioinate "Goyle", but "Goyle" definitely knows each of their names. Further analysis of the alias "Avery Etidorpha Wormwood" will reveal "Avery" to mean "wisdom of the elves", an interesting coincidence, but far from the most damning. "Etidorpha" is of immense note, likely a reference to a novel of the same name which was very popular at the time of it's release in the late 19th century. The book is a "Hollow Earth" adventure story. Across Scandinavian, Germanic and Celtic myths of the fae there exist entities who dwell in subterranean systems. That brings us to "Wormwood", a name rife with symbolism. Here I'd like to address one very popular use for the herb wormwood, also known as Artemisia Absinthium- did you catch that? ABSINTHium. The drink we now know as "Absinthe" is a toothless dachshunds compared to the concoction that earned it the nickname "Green Fairy".