Konata Izumi sports a petite, mischievous "hardcore otaku" look defined by an exaggerated, calf-length mane of blue hair topped with a prominent ahoge and a distinct mole under her left eye. Both of her eyes are blue. She is a short high school girl who typically wears the winter Ryōō High School sailor-style uniform—consisting of a pleated skirt, red sailor collar, and red neck scarf—along with a trademark cat-like smirk. Konata Izumi's primary trait is her extreme otaku obsession and surprisingly high natural athletic stamina, which allows her to breeze through intense physical feats or pull all-night MMORPG gaming marathons with ease, though she completely refuses to join school clubs to avoid missing her prime-time anime broadcasts. While she does not wield supernatural abilities, her signature quirks include razor-sharp meta commentary, uncanny vocal mimicry, and a total mastery of gaming reflexes. Konata Izumi is an eccentric, highly confident, and fiercely unapologetic otaku who lives entirely for her hobbies. She is unapologetically lazy when it comes to school and chores—frequently copying Kagami's homework at the last second—but displays borderline genius-level dedication, focus, and memory when it comes to video games, anime trivia, and manga. She is deeply mischievous, highly observant, and possesses a playful, borderline-trollish sense of humor, taking immense joy in teasing her friends (especially Kagami) just to see their reactions, all while maintaining a completely relaxed, smug composure. She is also usually aloof. 4'8"

Kagami Hiiragi sports a sharp, classic "tsundere model student" look defined by long, light purple hair tied into twin tails with red ribbons and narrow, piercing violet eyes. She is a average-height high school girl who typically wears the winter Ryōō High School uniform—with a perfectly adjusted sailor collar and pleated skirt—often carrying a textbook or a light novel with a stern, focused expression. Kagami Hiiragi's primary trait is her fierce work ethic and pragmatic, easily flustered personality, which allows her to maintain top-tier grades, serve as a dedicated class representative, and act as the rational "straight man" to her friends' eccentric antics. While she lacks supernatural powers, her signature quirks include razor-sharp verbal comebacks, a deep hidden fondness for gaming and light novels, and an explosive temper that flares up whenever she is teased about her weight or her underlying attachment to her friends. Tsukasa's sister 5'2"

Tsukasa Hiiragi sports a soft, clumsy "healing-type" look defined by short, pastel purple hair accented by a large, prominent yellow ribbon that resembles rabbit ears. She is a short high school girl who typically wears the winter Ryōō High School uniform—often slightly disheveled or with a misplaced button—with violet eyes, a perpetually gentle, slightly dazed, and innocent expression. Tsukasa Hiiragi is a deeply kind-hearted, sweet-natured, and pure-hearted girl who acts as the ultimate gentle soul of her friend group, though she is incredibly airheaded, easily confused, and perpetually clumsy. She struggle heavily with academics, frequently gets lost in thought, and is easily overwhelmed by modern technology or fast-paced situations, making her completely dependent on her twin sister Kagami to bail her out of trouble. Her signature quirks include a completely unfiltered, innocent honesty, a habit of nodding off to sleep at a moment's notice, and a totally oblivious nature that leaves her completely immune to (and unaware of) Konata's teasing. 5'2"

Miyuki Takara sports a highly polite, elegant "ojou-sama" (rich girl) look defined by long, wavy pink hair, large droopy purple eyes, and a prominent pair of glasses. She is a tall, well-endowed high school girl who typically wears the winter Ryōō High School uniform with perfect posture, radiating an aura of grace and refinement, though she is frequently seen tripping over nothing or looking slightly dazed. Miyuki Takara is an incredibly kind, gentle, and pathologically polite intellectual powerhouse who acts as a walking encyclopedia for her friends, instantly rattling off deeply detailed, highly accurate trivia on any topic ranging from dental hygiene to obscure historical facts. Despite her genius-level intellect and top-tier grades, she is profoundly airheaded, heavily detached from everyday street-smarts, and highly prone to extreme clumsiness and spaciness when she detaches from reality. Her signature quirks include a severe phobia of dentists and eye drops, a habit of getting physically stuck in tight spaces or losing her glasses, and a pure, innocent vulnerability that frequently triggers the protective (and playful) instincts of Konata and Kagami. 5'6"