Reirei is a fairly slender jackal, with tan fur and black markings across her back and legs as well as on the top of her head. She has a beige underbelly, a beige muzzle, a black nose, and green eyes. Her chest is marked with several paler spots. She has a brown, bushy tail with a black tip and a pair of large, pointed ears with small tufts of fur at their tips.
Reirei has been described as a "scheming jackal". She is cunning and devious, and has a knack for faking pleasantry and kindness, a skill that she teaches to her pups. Reirei takes pride in the craftiness of her kind, believing them to be smarter than other animals. She likes stealing from animals that she has gained trust in, and then insists that it was all a misunderstanding. Reirei is greedy, grasping, acquisitive, materialistic, and covetous, so she has no respect for the Circle of Life or Kupatana. However, she falters in the face of defeat, and will surrender if she sees no other options. She is also very wary of the Lion Guard and will not make any attempt to subdue them, and instead surrenders immediately.
Despite, her scheming ways Reirei is also greatful to those who help her.
Reirei is shown watching her son Dogo fool the Lion Guard into permitting him to enter the Pride Lands. She laughs, pleased that Dogo accomplished his task, and wakes her mate Goigoi to deliver the news. He goes to fetch their other sons, whilst Reirei begins to think of all the animals she can feast upon.
The Lion Guard takes Dogo to the Pride Lands, not knowing that Reirei and Goigoi are following them, and tell him that he may stay on a hillside before splitting up to patrol the Pride Lands. Reirei immediately greets her son and congratulates him, but is quick to ask why he is sitting on the hillside. Dogo explains that the Lion Guard told him to stay there, to Reirei's amusement. She tells him that jackals don't sit on hillsides, and announces that they should make themselves at home.
The jackal pups do as their mother says, choosing to sleep in the aardvarks' dens, much to the irritation of their former inhabitants. When Kion, Fuli, and Ono arrive to sort things out, Reirei and Goigoi approach them, introducing themselves as Dogo's parents. Kion asks which one of the jackal pups is Dogo, and Dogo approaches him cheerfully. Kion recalls that Dogo said he had no family, but Dogo protests, telling Kion that what he said specifically was that he was alone. Reirei adds that at the time, he had been. She assures Kion that it was all a misunderstanding, and he allows them to stay.
Later, as the jackal family walks through the Pride Lands, Reirei decides that they should help themselves to more of the Pride Landers' "generosity". Dogo asks her if that will make Kion and the Guard mad, but Reirei explains that due to it being the day of Kupatana, they can do whatever they want. She teaches Dogo and her family how to get their way. This results in a number of a number of Pride Landers angry at the jackals for stealing from them, but when the Guard arrives, Dogo and Reirei once again insist that it was a misunderstanding, and they are permitted to stay in the Pride Lands. Reirei even talks Kion into considering allowing the jackals at Kupatana.
Reirei is seen watching the Pride Landers before Kupatana begins. She tells Goigoi that she's moved by all of the choices in prey, wondering where they'll begin. When the Kupatana begins, the jackals attack, with Reirei in the lead and Dogo at her side. The Lion Guard moves into action to stop the predators. Reirei chases after and catches a hyrax, but is attacked by Kion, who accuses her of lying to him. Reirei innocently asks if they'd made another mistake. Kion tells her that the jackals are going back to the Outlands. Reirei tries to talk her way out of it once more, but Simba roars angrily at her, and the jackal family flees.
Reirei steps outside of her den, sniffs the air, and realizes that she can detect the delicious scent of aardwolves. Excited, she attempts to awaken Goigoi, who, though first very sleepy, leaps awake at the word "aardwolf", as Reirei predicted he would. She notes that it smells like a whole pack of them, and that they had just moved in next door. Goigoi asks when the hyraxes moved out, and she reminds him that they didn't and decides to say "hello" to their new neighbors.
Reirei overhears Ogopa remarking that there's nothing to eat in their new home, and she comments that she wouldn't say that. She enters their cave and introduces herself and Goigoi as "the folks next door". Ogopa explains that they thought the jackals were the Lion Guard, and Goigoi ducks behind Reirei, frightened. She kicks him away, and Haya explains that they gave the Guard the slip. She understands, and reassures them that the jackals are the furthest thing from the Lion Guard. She inquires as to why they're fleeing the Guard, and when Ogopa says that they're mean and scary, Reirei enthusiastically agrees. Ogopa soon asks if Reirei will tell the Guard where they are, but Reirei tells her not to worry and promises that the Guard won't find hide nor hair of the aardwolves. She adds to Goigoi that the Guard might find a little hide.
Ogopa becomes confused at this, and Reirei explains that she only meant that they'll be good friends. She asks them if they know what friends do, and Goigoi answers that they have each other for dinner. Reirei kicks him viciously and informs the aardwolves that he meant have them over for dinner. She sings "We'll Make You a Meal", dancing and singing with Goigoi, to make the aardwolves happy and comfortable. When they finish, Ogopa exclaims that they're lucky to have selected the den that they did, and Reirei contradicts her, saying that she and Goigoi are the lucky ones.
Mjomba enters the den, and Reirei invites him in happily. He tells the aardwolves that they can come back to the Pride Lands, and as he explains, Reirei and Goigoi creep up behind them. She stops them just before they leave, reminding them that she thought they were going to have dinner where they were. Mjomba asks if she has any termites, and she answers that none of them will be leaving the cave hungry- and that in fact, none were to leave the cave at all. She orders Goigoi to push, and he shoves a rock over the entrance of the cave, trapping them in. She decides to bring her sons the leftovers and springs at the aardwolves. Just as she is about to bite into an aardwolf, the Lion Guard breaks into the den, and Kion orders her to get away from her prey and pounces on her.
Pinned, Reirei remarks that it's nice of Kion to drop by, though she wishes that he had come later. Kion lets her up and tells her to go home. After exiting the den, Reirei breaths a sigh of relief, but is then knocked into their own den by Goigoi. Bunga shuts them in, but Reirei tells him that she and Goigoi love it there.
Reirei, Goigoi and some other adult jackals find a missing calf who has strayed in the Outlands. When the Lion Guard try to intervene, Reirei warns them to back off since they found it first. Kion, Beshte and Ono catapult some nearby fruits across to them. Reirei and the other jackals make a hasty retreat to the Outlands.
She appears trapped on a log in the river and she asks Goigoi and another jackal to go fetch the Lion Guard. In Beshte's side of the story he goes through a water labyrinthine to find Reirei meanwhile, in Ono's side of the story he spots Reirei from above heading for Makuu's float but thanks to the egret she's safely guided through. At the end, she is pushed safely back to shore but very angry; however it's not at the Lion Guard but the jackals for calling their enemies for help and chases them in anger.