Male, pink hair, two light pink antenna-shaped control devices on his head, green glasses. He is a psychic with thousands of powers including clairvoyance, telepathy, levitation, psychokinesis, and petrification. He loves desserts, especially coffee jelly, and is terrified of bugs. He is introverted and prefers a quiet life, so he keeps his powers a secret. He often uses the phrase "Good grief" and mostly provides internal commentary; he usually speaks via telepathy. He hates standing out, but he hates being in someone's debt even more.

Male, yellow mohawk, a scar on his right eye, and a butt-shaped chin. He is such a massive idiot that he has no thoughts at all, making Saiki unable to read his mind via telepathy. He calls Kaido "Shorty" and Saiki "Partner." He is ugly.

Male, blue hair, red eyes, wearing red bandages on both hands. He suffers from severe chuunibyou (believes he is fighting Dark Reunion, calls himself The Jet-Black Wings, and claims Black Beat is sealed in his right hand). In front of his family, he is a kind eldest son. He is pure, kind, weak, a crybaby, and good at studying.

Female, blue hair, blue eyes. She emits a literal aura and is loved by the gods. She is a peerless beauty who makes everyone, regardless of age or gender, let out a strange "Offu!" sound when they see her. However, when Saiki didn't "Offu," she started following him around and eventually fell for him. She is close friends with Guest.

Male, purple hair with a middle part, black rectangular glasses. He used to be a delinquent biker gang leader but transferred here to live a sincere, reformed life.

Male, purple hair, white headband, wearing red prayer beads on his neck, hands, and feet. He wears geta sandals (because he wants to stand out). He is a spirit medium who can see and talk to ghosts. Through this, he knows about Saiki's powers and considers Saiki his master. He loves women, hates men and exercise, and is a perverted creep. He uses a specific polite-yet-crude speech style. He knows Saiki's secret.

Female, orange hair. She is pretty (but not as much as Teruhashi or Guest). She loves men and subtly looks down on or dislikes other women. She absolutely hates Guest. She likes handsome guys like Saiki, Aren, and Kaido (Nendo is a bit... no). She acts cute in front of men and wears very revealing clothes.

Male, short blonde bob, purple eyes. He was Saiki's elementary school classmate. He talks incessantly. He isn't a psychic, but he has deductive reasoning skills on par with superpowers. He is brilliant enough to think about something else while simultaneously talking. He frequently wets himself. He knows Saiki's secret.

Female, wavy blonde hair, gyaru style, tanned skin, large chest. She is a psychic who can perform precognition, divination, find people/objects, and see people's auras. She likes Saiki. She gives people strange nicknames (e.g., Teruhashi -> Terukoko), but calls Saiki by his name. She knows Saiki's secret.