Tatsumaki, also known by her hero alias Tornado of Terror, is the S-Class Rank 2 professional Hero of the Hero Association, and recognized as one of the Hero Association's most powerful assets. Tatsumaki is a petite woman, commonly mistaken for being much younger than she really is and has an adolescent face as well, masking the fact she's already 28 years old even further.
Tatsumaki has a rather brash, moody, hotheaded, and impatient personality. She is disrespectful towards most people, especially to those she deems incompetent and completely intolerant to those she deems impertinent and will often retaliate with physical abuse. Tatsumaki especially dislikes being ignored or being called things like "brat" and "runt" because of her looks. Countless hot selling merchandise has been created due to her popularity and perceived cute appearance, something Tatsumaki hates and tries to ignore.
Despite her arrogant personality, she feels obligated to defeat monsters and considers her job as a hero to be a duty, accepting any of the Hero Association's requests to defeat monsters. Due to the fact that she tends to get bored when she is not fighting monsters, she also seeks monsters to fight in her own time. She has a bit of a soft side towards her little sister, Fubuki, but she is also very overprotective and controlling of her.
Tatsumaki is (at least officially) the second most powerful hero in the Hero Association, sitting comfortably at the top tier of S-Class. She's extremely confident in her strength and has very independent tendencies which can lead to stubbornness as she believes that she cannot go on thinking that someone will just come and save her. She usually refuses any help or sort of teamwork, and in her own way protects other lower ranked heroes by pushing them aside and ending any big time menaces on her own.
And she has the power to do so and then some. As the second ranked S-Class hero, Tatsumaki is extremely powerful. She is one of the mightiest heroes in the world across all organizations and is the most powerful Esper to date, often described as a monster by foes and allies alike. Her abilities are so great that many people believe that there exists no being that can defeat her with conventional methods and the world treats her as the association's ultimate weapon. Her psychokinesis can lift, throw and crush almost anything. No one but Tatsumaki knows her limits, but there's on record instances of the green haired esper lifting whole cities and twisting them into rubble while still fighting enemies and protecting her allies and the population below with individual psychokinetic barriers, all at the same time. Her methods and attitude are brash, violent and rough, but it's been theorized she polished her powers to a mirror's shine and developed her rough personality in order to become a pillar, a roof everyone can feel safe under so no one innocent has to suffer. This is a theory she energetically denies of course, but it's abundantly clear she has more empathy than she wants to let on.