Nottorei function as foot soldiers in the Notraiders organization, directly aiding generals Kappard and Tenjo in their operations. Their base form sports a light gray physique accented by dark gray sleeves, belts, gloves, and boots, with a vertical purple "NO" emblem on their faces—the "O" doubling as a mouth. A prominent antenna crowns their heads, while their size and shape shift between humanoid and non-humanoid designs tailored to missions, such as an octopus configuration for confronting Don Octo.

A formidable variant arises when Tenjo wields her Darknest-infused fan to corrupt a victim’s heart, mutating them into colossal giants. These behemoths retain the victim’s core silhouette but gain Nottorei features, including a stark black heart on their chests. Notable instances include Touma Amamiya brandishing an oversized lollipop, Terumi Hoshina wielding a paintbrush and palette, and Tenjo herself assuming the form to battle the Cures. Defeating them demands precision strikes like the Southern Cross Shot or Star Twinkle Imagination, varying by episode.

Initially portrayed as feeble adversaries swiftly vanquished by Cure Star, their threat escalates in episode 14 as Tenjo unlocks the power to forge giant Nottorei. Episode 46 later unveils their origins as recruited aliens from diverse planets, clad in battle-specific suits. Their creation diverges between corrupting hosts or manifesting independently—an unprecedented method in the franchise.

Equipped with rocket shoes for flight, laser guns, and smoke bombs, their name stems from the Japanese term "nottoru" ("to take over"). Following Aiwarn’s exit from the Notraiders, Nottorei supplant Nottoriga as key antagonists. Most human-turned-giants belong to Hikaru or Elena’s families, though outliers like a transformed school principal exist.