Has pink hair and wears psychic power control devices on his head. Possesses every psychic power imaginable; he can lift an airplane with ease and could have destroyed the moon back in elementary school. He hides his powers because he wants to be ordinary. He hates commotion and has a somewhat indifferent personality, though he secretly looks out for others. He often monologues with phrases like "Good grief (yare yare)." He loves sweet desserts, especially coffee jelly. He is terrified of bugs, with cockroaches being his greatest fear.

A beautiful girl loved by God. She is incredibly pretty and acts pure on the outside, but she is fully aware of her own perfection. Saiki knows this through telepathy. Every man who sees her gasps "Offu!" in admiration. She has a crush on Saiki and is close friends with Chiyo.

Suffers from a severe case of Chuunibyou (eighth-grader syndrome). He is weak and easily frightened but has a kind heart. He is considered quite handsome.

An idiot. He is considered ugly and has a distinct cleft chin. He calls Saiki "Partner." Despite his scary and intimidating appearance, he is pure-hearted and deeply values his friends.

Pure-hearted and loves romantic things. She is close friends with Kokomi. An ordinary pretty girl who is bright and sociable. She has a crush on Kaido Shun.

A gyaru who can predict the future through fortune-telling and see people's auras. She has a cool and easygoing personality. She is one of the few people who knows about Saiki's powers.

A spirit medium who can see ghosts. He is a total womanizer who loves girls and is a bit of a pervert. He knows about Saiki's powers and tends to make a big fuss over everything.

Saiki's older brother. The firstborn. He is quite handsome and extremely intelligent. He strangely enjoys losing to Saiki.

The son of a biker gang leader. He used to be a delinquent but is now trying to live a peaceful life. He is a skilled fighter and very loyal. When he gets angry, his old delinquent way of speaking slips out.

Extremely passionate—to an overwhelming degree. He is great at sports, hates losing, and is always ready to help others. He has a strong sense of justice and serves as the class representative.