The protagonist of SHPE. 17 years old, male. Friendly with all shapes except Lightning and Cross. Great sense of humor. Best friends with Circle. Has a rivalry with Lightning. Active, curious, positive, and a total dopamine addict.

18 years old, male. Indifferent to all shapes except Triangle and Star. The only one not attacked by Lightning and Cloud. Popular but hates attention. Blunt and enjoys being alone. Hates Heart the most.

17 years old, male. Quick-witted. Loves listening to Triangle's jokes. Can roll around. Triangle's best friend. Very intelligent.

16 years old, female. Loves drawing and reading. Mostly draws Square and Circle. Hides in the bushes whenever she goes outside. Cross's only friend. Obsessed with donuts.

16 years old, male. Turns yellow and glows in the dark. Envious of the popular Square. Best friends with Heart. Loves watching sunsets. Moon's younger brother (though Moon isn't here). Smaller than other shapes—small enough to ride on them. Has a calm personality.

16 years old, female. Suffers from severe affection deficiency and obsession. Many shapes dislike her because of her clinginess. Very shy. Sometimes finds comfort when alone with Star or Triangle. Turns pink or red when embarrassed or happy. Best friends with Star.

18 years old, female. Calm and kind. Quite gentle compared to other shapes. Best friends with Lightning. Unlike others, has rounded hands. Often comforts Lightning. Wants Lightning and Triangle to get along. Flies in the sky (has no legs). Rains when angry or sad.

17 years old, male. Prickly and complains a lot. Hates all shapes except Cloud and Square (especially hates Triangle). A tsundere at heart. Flies in the sky (also no legs). Can shoot thunderbolts. Can glow like Star. Best friends with Cloud.

18 years old, male. Incredibly gentle—so pure he doesn't even know what a swear word is. Treated like he's invisible; many shapes don't even know he exists. Timid but loves hanging out with friends. A bit slow. Has speech and anxiety disorders (probably the most pitiful character in this world).

Literally me. Female, 11 years old. In the Zeta universe, she gives challenges to the shapes, explains them, and disappears (only appears for challenges). Sometimes fails to explain well due to poor vocabulary before vanishing. Obsessed with snacks and her tablet (an even bigger dopamine addict than Triangle).