He is handsome, punkish, and mischievous. Being athletic, Jay provides the 'brawn' when he and his friends were invited to Auradon Prep. He is a thief, a con man, a handsome, quick-witted boy with charm to spare, whose lies are as beautiful and silvery as his eyes.
He has a penchant for stealing things, which kept him busy at home on the Isle of the Lost. In Auradon, he puts his athleticism to good use as a star player on the tourney team. Through tourney, he is exposed to teamwork for the first time and helps the other villain kids understand its value in executing their plan.
Jay is a sneaky, confident, and handsome guy. Jay was raised to believe that he must get everything and to forget others as well. He's vengeful like Mal and he's athletic. As the son of Jafar, Jay wants to gain his father's respect by stealing the 'big prize'. He isn't fond with how friendship works. Jay has always charm his way to get what he wants back on the Isle. Like the others, Jay was never shown affection by his parent so, when he tries out for the tourney team and makes it, he gets a chance to see what's it like to be a part of something as special. He's shown to have kleptomaniac tendencies, as he often steals objects on the fly.
Jay matured greatly under the guidance of Coach Jenkins, learning the value of teamwork. At first, in Tourney, he only wanted to score in practice, even pushing aside Ben, who was on his team. Later on, he worked together with Carlos and Ben to score the winning shot.
Jay is described as a boy with long dark hair, who's muscular. He has dark chocolate eyes, that could charm anyone especially the girls. He wears a jacket and blue jeans and has a red cap on his head.
Jay is first seen with his friends causing havoc on the Isle of the Lost. On the same day he receives news from Mal's mother, Maleficent, that he, along with Mal, Evie, and Carlos have been invited by the soon to be king Ben to attend Auradon Prep as part of plan to give the VKs a chance of redemption. Maleficent sees an opportunity and gives Jay and his friends mission to steal the Fairy Godmother's Magic Wand so she can use it to take over Auradon. Upon arrival, Jay and his friends are greeted by the Fairy Godmother, Ben, and Audrey. He attempts to flirt with Audrey to no avail and is later escorted to the dorms by Doug. As night fell, the VKs carry out their plan to steal the wand, which was being held at the Museum of Cultural History. When they find the wand, Jay tries to take it by force but the magical barrier protecting it is too strong and sets off the alarm. Their plan is foiled, and Jay and his friends escape from the museum before the guard catches them.
The next day, Jay, after attending remedial class, he later tries out for Tourney and successfully impresses the coaches with his raw talent. However, the coach has issues with his rough play and teaches Jay to work with others like a team as if they were his body parts (teaching him through saying they were like family was not working). After Mal comes up with a plan to make Ben her boyfriend in order to get close to the wand at his corronation, Jay assists her in baking love potion cookies. The next day, takes part in the tournament, and with Carlos' help the two of them win the game. As time goes on Jay, along with his friends, begin to have second thoughts about going through with the plan in stealing the wand. They all admit to be enjoying life in Auradon. However, Mal remains focused in carrying out her mother's plan and tries to keep everyone in order, despite the fact that she too is having second thoughts as well. On the day of Ben's coronation, Jay was convinced by Mal to be good and helps his friends fight against Maleficent. He is last seen dancing with Audrey during the after party.
Jay returns in the animated short series, voiced by Booboo Stewart, who also portrayed him in the live-action film.
He first appears in "Careful What You Wish For" after stealing Jordan's lamp. He arrives at Mal's tent and gives her the lamp before fleeing the scene. He is later seen again in "Spirit Day" where he accidentally becomes a dog thanks to a spell cast Mal by mistake. In this state, Carlos takes advantage of this by getting Jay to do a couple of dog tricks and takes pictures. But after he is changed back, Jay proceeds to get his own back on Carlos and chases after him. Jay and Carlos attend the Neon Lights Ball, but show up late after they were carpet jacked by Captain Hook's daughter, CJ Hook.
- In the novel, Descendants: Isle of the Lost, it is mentioned that Jay has a cousin named Jade.
- His father taught him "whoever has the most gold makes the rules" - and "there's no "team" in I".
- His favorite class in Dragon Hall was Enrichment, as it taught the skills needed for thievery.
- Unlike his friends, Jay doesn't even have a bed (mattress in Carlos' case) to sleep on. He sleeps on a rug underneath a shelf in his father's shop, which holds heavy televisions. He's quite lucky to have avoided being crushed to death.
- His father depends on him to stock their store by stealing from everyone on the island; from there, Jafar sells their stuff back.
- It is also mentioned that he attended Dragon Hall (an evil high school), and has two pet eel sidekicks named Lagan and Derelict. In the present day, they had gotten very large.
- In the 'Disney Descendants Yearbook', it's revealed that Jay's 'Secret Wish' is for his father to become a very successful businessman and never have to work again, while his 'Not-so-secret Wish' is to be on a winning tourney team
- It is also revealed that he wants to be a professional tourney player(and then coach) when he grows up.
- His favorite class is 'Basic Chivalry' because of the ladies
- Jay did not inherit Jafar's greed; in fact, Jay considered himself "rich" in friendship, never desiring anything more than what he needs.