Prior to the start of the Sun, Moon, Ultra Sun & Ultra Moon chapter Quarter was raised by Lana alongside many other Wishiwashi to be the Totem Pokémon of Brooklet Hill. They eventually became too powerful for Lana to handle and begin causing havoc on anyone they could.
Quarter first appeared in True Identity and the Totem Pokémon of Brooklet Hill at Brooklet Hill, helping Sun recover his 1 yen coin. Glad for the help and worried the 8 meter Totem Pokémon might eat Wishiwashi Sun decides to add him to his team and names him Quarter, though he decides he can catch him in a Poké Ball later. Sun then asks Quarter to take him to the Totem Pokémon and the two head out into the water. After searching for hours Sun is still unable to find the Totem Pokémon and decides to join Quarter in the water. Underwater he sees a lot of Wishiwashi and questions why Quarter brought him to his habitat. Dollar attacks Quarter and he swims away, but comes back after activating his Ability Schooling. Seeing the School Form Wishiwashi in front of him Sun realizes that Quarter and the other Wishiwashi are the Totem Pokémon.
Quarter attacks Sun and Dollar with Water Gun, taking Dollar out of the fight. Sun switches for Cent just as Quarter fires another Water Gun and hits with Aqua Tail. This enrages Cent and he begins furiously attacking the Wishiwashi, but Quarter and the group easily push Cent back. Hoping that defeating the leader will disperse them Sun tells Cent to attack Wishiwashi's left eye, as that is where Quarter is located. Quarter attacks with Water Gun and Cent avoids it, but is then immediately hit by Wishiwashi's tail. Cent uses the momentum to get close to the left eye and slash it, breaking apart the Wishiwashi. Having a better understanding of each other Sun asks Quarter to join his team again. Agreeing to join him Sun catches Quarter.
In Shipwreck and "Oh, What Sharp Teeth You Have, Bruxish!", Quarter helped rescue Lillie from an attacking Bruxish. Using his Schooling Ability Quarter summoned many Wishiwashi and turns into his School Form and grabs Lillie in his mouth. After securing Lillie he attacks the Bruxish and defeats it. Sun and Lillie later wash up on a beach, with Quarter back in his Solo Form, and are rescued by Acerola.
In Truth and the Mastermind Behind Team Skull, Quarter, along with the rest of Sun's team, helped to rescue Moon from an attacking Xurkitree. By combining their attacks, they managed to knock Moon from Xurkitree's grasp, though Xurkitree immediately retaliated by smacking them away onto a nearby car.
In Darkness!! The Mysterious Claws of Necrozma!, Quarter was used alongside the rest of Sun and Moon's teams to assist Lunala against Necrozma, but was stopped by Lusamine's Naganadel.
After returning to Alola, Sun finds Necrozma, who wants to absorb the light energy from the region. Sun sends out his team to attack, who get thrown back by the Prism Pokémon. This causes Dollar to evolve into Incineroar, who manages to push it off a cliff. The group goes after it on top of Drachma, though it easily pushes them back, save for Drachma, who is able to use its large body to hold Necrozma down.