Warning: This profile contains spoilers for The Raven Cycle.
“Actually, I don’t care about that. I mean, the cards are very interesting and I don’t want to discount what you do. But I didn’t really come here to have my future told to me. I’m quite okay with finding that out myself.”
Gansey is a kind, charming, intelligent individual. In terms of personality, there is noted to be—particularly by Blue—"two Ganseys". One is a fragile, slightly eccentric, passionate young man who is dedicated to his dogged search for an ancient Welsh king, is an insomniac, chews mint leaves, drives a loud orange Camaro, and has a miniaturized model of Henrietta in his apartment. The other is a charismatic man who can socialize easily and manipulate others, ruling as a “king” of Aglionby Academy. This difference is said to be visible in his expression.
However, Gansey has shown himself to be a caring, loving friend. He did not desert Ronan when the latter became reckless and violent, after his father’s death, and often covers for him and fixes his mistakes. He stands by Adam even when they argue bitterly over Gansey’s money and Adam’s abusive home life. He gives Noah his own room in Gansey’s home, Monmouth Manufacturing, even though the former is rarely there.
As a child, Gansey—who has a deadly allergy to wasps—stumbled across a nest of them in the woods, outside of his family home. He was viciously attacked, but, as he lay dying, he heard the words: “You will live because of Glendower. Someone else on the Ley line is dying when they should not, and so you will live when you should not.” Gansey miraculously survived this encounter—though it left him traumatized—and it sparked his intense desire to find the ancient Welsh king, Glendower.
Gansey went to a variety of different high schools during his teenage years; though, never for long. He leapt from place to place, often following the Ley lines, continuing his research regarding Glendower. These travels lead him to various places around the world, including Britain, where he met Professor Mallory, a supernatural enthusiast who had was sensitive to energy, and had already conducted his own research into the Ley lines. He stayed in Britain for a fairly long amount of time; however, one day, while traveling along a line with Mallory, he suffered a panic attack, triggered from the memory of his near death experience. This event haunted Gansey; later, he got into a terrible argument with Mallory, and left without a word.
At some point, his travels took him to Poland, where he met a man who was able to follow the directions Ley lines, as long as he was singing—a memory Gansey later recounts to Blue.
Eventually, Gansey came to Aglionby Academy, in Henrietta, West Virginia. He purchased an abandoned building, Monmouth Manufacturing, converting it into his home. There, he met fellow student Ronan Lynch, the son of wealthy Irishman Niall Lynch; the two became close friends, despite their seemingly clashing personalities. Gansey helped Ronan survive his father’s traumatic murder, allowing the latter to move into Monmouth Manufacturing with him when he was forbidden from returning home.
Later, Gansey met Adam Parrish, a local boy who had gained a scholarship to Aglionby. They became good friends—despite Ronan’s displeasure—and their contrasting backgrounds, though, the latter remains a point of contention between the two.
At some point, Gansey met Noah Czerny—who he assumed was a student—and befriended him; eventually, Noah moved into Monmouth Manufacturing, with Gansey and Ronan.