ChuChu is a pink Flapjack octopus with a large red bow on the back of her head, has rosy cheeks, and has purple eyes (silver in the opening of Kirby's Dream Land 3 and blue sky in Kirby Star Allies). She is infatuated with Kirby and it is implied that she is a romantic interest. Although sweet to Kirby, she is shown to be very short tempered with the other animals.
ChuChu, as well as all the other animal friends, have the ability to share and enhance whatever ability Kirby currently has. When Kirby is paired with ChuChu, she can swallow enemies while underwater, and ChuChu has her unique ability to stick onto ceilings and "walk" on them, but she can't do the same with walls. Her best friend is Nyupun.
Similar to the Laser ability from Kirby's Adventure, but continues after damaging an enemy or block. ChuChu charges up electricity in one arm, eventually releasing it. This beam will bounce off hills and walls if it is charged, with the number of bounces being determined from the charge time.
When the player mixes the Stone and Cutter abilities, Kirby gains the mix ability Animal Statues, which lets him turn into statues of any of his past animal friends, including ChuChu. Kirby can hop around when becoming this statue.
ChuChu's likeness is used for one of the sets of GearDoctor Healmore can obtain. Kirby can purchase and use the Chuchu Flask and Chuchu Cap from the Shoppe; the cap implies to be ChuChu herself, as it even moves and blinks (although the game jokingly states this is "a trick of the light").
ChuChu appears as a Novice-class support spirit in Super Smash Bros. Ultimate which can be obtained after fighting Jigglypuff on the Dream Land 64 stage with sticky floors. When applied to a fighter, the fighter will have a Super Leaf equipped.
ChuChu's name may be derived from the Japanese onomatopoeia chu, the sound of a kiss; it may also be derive from tutu, a short skirt worn by ballerinas. These could be in reference to her femininity, with the latter also referencing her general shape and possibly color.
A flask that calls to mind a mysterious girl. The power of love that it holds heightens a number of abilities.”
Modeled on a stalwart companion from another adventure. If it seems to move on its own, that's just a trick of the light.”
— Armor Description • Team Kirby Clash Deluxe
Many of ChuChu's abilities revolve around either Kirby and her holding hands, or spinning while looking in each other's eyes, as well as the duo constantly giggling as if content with each other's presence. This is used to guess at a romantic relationship, which became a running gag in the (non-canon) manga where she is shown to have a crush on Kirby. In addition, one of the level intros shows Gooey flirting with ChuChu and her reacting violently, and another shows ChuChu and Kine fighting over Kirby's companionship.
Unlike other animal friends, who inhale enemies or have Kirby inhale them, ChuChu reaches out her arm and if she catches an enemy, she drags it into Kirby's mouth; essentially, using ChuChu gives Kirby Gooey's tongue-lash in place of an inhale.