The Main 6 of Blue Horizon's character profiles on the main comic site, transcripted on Neocities.

Antonio Chandrani-Rivera:

The true eldest of triplet brothers, Antonio has long been regarded as "infamous" by the world population. Like his twins, several cousins, and Alejandro Altaha, at 15 he joins the Protector's class with the goal of becoming the Protector of Worlds... They say he's secretly planning on bringing Alejandro Altaha down. How far will he go for the sake of his goals?

Among Antonio's friends he's known as straightforward, brash and a little too frustrating. Unlike his identical twin Fernando he easily loses his cheeriness, having a tendency toward broodiness. This is something his taciturn fraternal twin Raj is very inclined to too, though Raj is much quieter as a person.

Antonio is particularly known to flex his beauty and boast about his accomplishments.

[English-style] pronouns: Antonio doesn't understand.
Sexuality: Gay
Special item: A broken spring green plastic ring with a half-torn green cloth flower.
Likes: Libraries; history; astronomy; complicated puzzles; flashy rings; being around confident and calm guys; having female friends.
Dislikes: He won't disclose these.

Alejandro [Caldera-]Altaha:

A confident individual who rarely falters on whatever path he's bent on taking, even if it meanders or causes him to become lost. Initially Alejandro isn't interested in the position of Protector.

People easily relax around him, and many notice his underlying warmth. This is how he becomes close confidants with the likes of the cheery and reliable Fernando Chandrani-Rivera, the easygoing and amiable Diego, as well as the sharp and capable Alia [Atif-]Akinyemi.

Despite Alejandro falling in with people easily, he winds up having trouble around Antonio Chandrani-Rivera. Yet everyone knows that Antonio Chandrani-Rivera is too often around him at 15 years age.

Among all his friends, Alejandro is regarded as rather hotheaded and occasionally a little clueless. He's one of the most honorable of students in the Protector's class, though it doesn't mean he can't be deceptive. He likes to be around steadfast people.

[English-style] pronouns: Grew up with "he/him."
Sexuality: it is a mystery (not hetero)
Special item: A carefully-kept photograph.
Likes: Libraries; history; math; eating healthy; sweets; close confidants; living freely; being nosy.
Dislikes: Saviors; familial problems; his brother; worrying about love; bitter foods.

Layla Chandrani:

Layla Chandrani is most well-known among the all-female and nonbinary-adjacent Queen's Guard as a thunderous individual, though their powers extend far beyond that of lightning and thunder. At 17 years age, they are the most powerful among the youngest generation of Chandrani progeny in the Protector's network and have little trouble showing it.

Despite being regarded as a little too easygoing and something of a cad among sapphics their age, they strangely avoid dating. Layla is known to seek out Alia Atif-Akinyemi, the most powerful young woman in the Queen's Guard, though whether they are truly friends is a puzzle amid many people's speculation. In the end, they call another young woman, the one very well-favored as the future Protector of Worlds—if she weren't interested in another position altogether—the one and only Khalida Ahmad, their 'best friend.'

[English-style] pronouns: Uses "she/her" growing up. Adds "they/them" when older.
Sexuality: Lesbian
Special item: A pale diamen-steel axeish thing they can fly around on. It has spring green designs like leaves on it.
Likes: Downtime; befriending girls; avoiding girls; configuring the future; testing their capabilities.
Dislikes: Keya; their datelessness; people who don't aim higher; familial trouble; Antonio running towards trouble.

Alia [Atif-]Akinyemi:

Alia Atif-Akinyemi is the most powerful young woman to be a part of the all-female and nonbinary-adjacent Queen's Guard. Her mother is famous, and she and her siblings are seen as individuals who will ascertain that the Atif name is respected across the planet Imion. At 17, she is the up-and-coming powerhouse of the Atif-Akinyemi clan with the strength of the stars that reflect within her seas.

What most note about her from the get-go is her coolness, though she is more extroverted than her younger brother Khaleel Atif-Akinyemi. She can be rather bold and to-the-point, which leads her down paths many have to chase after. Khaleel often wants to make sure his sister is doing alright, and tails her for that reason.

She seems surprisingly closed-off from Layla Chandrani despite being seen around her often, though a majority of students know that she finds Layla Chandrani very capable. She regards Khalida Ahmad as her closest.

[English-style] pronouns: She/her.
Sexuality: it is unknown (not hetero)
Special item: A book she's had for a while. It's unopenable.
Likes: Being Khalida's Second; libraries; ascertaining the future; understanding her capabilities; her trio of siblings.
Dislikes: Layla running after trouble; someone far apart; otherworldly shenanigans; an old friend; prophecies.

Khaleel Atif-Akinyemi:

Khaleel Atif-Akinyemi is more quiet and—at 16—more unassuming than his older sister Alia Atif. While his elder sisters are associated heavily with their mother and seen as people who will attempt to uphold their mother's reputation, Khaleel is more of a daddy's boy. Despite his relationship with his father causing him a great deal of consternation and leaving him with internal conflict.

Khaleel was childhood friends with Leo. He attempts to stay low-key, and yet more than a few have guessed that he is in love with him. Their current relationship is more at odds, though the Protector's network assumes they are close friends again due to the outward warmth they have around each other. It's the strangest thing.

He's fond of Antonio Chandrani-Rivera, and considers Alejandro Altaha his friend.

[English-style] pronouns: He/him.
Sexuality: Gay
Special item: A letter with a promise. The letter seems to have been crafted by a child with gray unknowable squiggle text, and there's a rainbowy word on it. There's two little brown-skinned children with black hair at the bottom drawn with happy anime eyes.
Likes: Upcoming.
Dislikes: Upcoming.

Leo Abara:

Leo Abara is known as quite friendly, and yet many gauge it, his sharpness. Raj assesses the 16-year-old Leo to be an up-and-coming leader.

He's rather calm and gets along with people well. Not only do people gather at his side easily, he's known to be quite the flirt, alike to Layla Chandrani but toward a wider range of genders. Antonio and Alejandro have small crushes on him; Leo mostly avoids flirting with them.

While he's among the most powerful in the Protector's class, it's been observed, how he's quite careful and avoids being over-flashy. To an extent, at least.

His relationship with Khaleel is quite curious. Alia regards him as an old friend, though in the end, both know about the trouble between the Atif-Akinyemi and the Abara families.

[English-style] pronouns: He/him.
Sexuality: Bisexual
Special item: A possibly ancient map with light obscuring it, as well as some sort of magical ward shown via rainbowing glitter that obscures the rest of it.
Likes: Upcoming.
Dislikes: Upcoming.