Kusuo Saiki is a male high school student, initially 16 and later 17 years old, born on August 16th to parents Kuniharu and Kurumi Saiki, with an older brother named Kusuke. Possessing a vast array of psychic abilities since birth, these include telepathy, psychokinesis, teleportation (which requires a 3-minute cooldown), clairvoyance (activated by crossing his eyes), invisibility (lasting 10 minutes unless touched), restoration, hypnosis, and transformation into any living being (limited to 2 hours per transformation). His female form is known as Kuriko (previously Kusuko), and his cat form is called Psi. These powers manifested early: he spoke via telepathy at two weeks old, walked and flew at one month, and began running errands by age one. To manage these abilities, he relies on specific restraints. Green-lensed glasses prevent him from involuntarily petrifying others through eye contact. Antenna-like "limiters," developed by his brother Kusuke, suppress his powers to manageable levels; without them, catastrophic accidents could occur. He also wears invisible gloves to block psychometry. Despite his immense capabilities, Saiki deliberately underperforms academically and physically to maintain an average appearance, copying test answers to achieve median scores and avoiding sports to prevent accidentally harming others. Personality-wise, Saiki presents as stoic, cynical, and reclusive, prioritizing anonymity and routine. He communicates almost exclusively via telepathy to avoid attention, frequently using the phrase "yare yare" ("good grief"). His constant telepathic exposure to others' unfiltered thoughts fosters misanthropy and social withdrawal. Yet, he demonstrates consistent compassion: he despises burdening others or incurring debts, actively intervenes to protect peers' well-being (such as shielding classmates from bullies or manipulating romantic outcomes), and values family loyalty, defending his father against criticism despite finding him embarrassing. Key traits include a terror of insects (especially cockroaches), an obsession with coffee jelly that overrides his usual restraint, and admiration for the mundane normality exemplified by his classmate Hiroshi Satou. Saiki's background involves early challenges. His transformation ability caused him to be born appearing female before shifting to male. Media scrutiny arose in kindergarten when his unbeaten streak at rock-paper-scissors led to rumors and a teacher's violent outburst. At age four, he inadvertently erased an entire nation pursuing him. These events cemented his desire for secrecy. He enrolls at PK Academy to blend in but attracts eccentric classmates, including the thought-blocking Riki Nendou, the delusional self-proclaimed "hero" Shun Kaidou, the narcissistic Kokomi Teruhashi, and the perverted medium Reita Toritsuka. His character evolves significantly. Initially dismissive of friendships, he gradually accepts his classmates as companions due to their persistent inclusion of him, though he conceals his powers to avoid burdening them. In the finale, Kusuke provides a device that removes his powers, fulfilling Saiki's wish for normalcy. However, he struggles profoundly with this loss, rendered unable to anticipate dangers like surprise attacks. His powers eventually resurface, revealing his physiology has fundamentally adapted to them. He chooses to resume wearing his limiters and glasses, acknowledging his need for both his abilities and the relationships he formed. This marks his progression from resenting his powers to accepting them as integral to his identity.