Irina Jelavić

Irina Jelavić (イリーナ・イェラビッチ, Irīna Yerabicchi) is the language teacher for class 3-E of Kunugigaoka Junior High School. She is actually a professional hitman hired by the government to assassinate Korosensei.

Appearance
Irina is a beautiful young woman. She has long blonde hair and blue eyes. With an ample bust and a curvy physique, she has a very seductive body that she utilises to seduce and manipulate her assassination targets. Irina is usually seen in fashionable clothing which emphasizes her flattering form though Karasuma regularly reprimands her for wearing "inappropriate" clothing for a teacher, forcing her to change into a more conservative apparel.

History
She is a well known hitman by the government. She has a proven track record of 11 jobs in countries around the world

Abilities
Infiltration: As an infiltration assassin, Irina is considered second to none. She is able to charm her way into her target's inner circles, penetrating the highest security and killing them when they're alone at point-blank range with little difficulty. Irina is seen to be able to adopt different personalities in order to infiltrate into the various situations

Linguistics: Irina is extremely skilled in conversational abilities being able to speak fluently in 10 separate languages. Through these skills combined with her infiltration abilities, Irina is able to extract information from her targets.

Martial Arts Competence/ Weaponry Master: Being an assassin, Irina shows considreable expertise when handling weapons such as guns, knives etc. She's also shown her abilities when setting up complex trigger traps when attempting to kill Korosensei. She shows able skills in martial arts but is still underskilled compared to more prominent assassins in the series such as Karasuma.

Other abilities: Irina is also seen to be able to play piano at a concert-performer level with ease while still being able to draw people's attention through miniscule body movements.

Relationships

 * As we know from before, Irina is most talented in her seductive skills which she used to accomplish her job as a hitman. So basically, Irina has had multipile relationships with men, where they were just a part of her mission.
 * With Koro-sensei: Koro-sensei is a target to be killed. Most of the time, Irina will endlessly try to stab Koro-sensei, whom easily evades her attacks.
 * With Karasuma Tadaomi: Since the middle of the manga, Irina was shown clinging to Karasuma (and trying to seduce him). Later, it is revealed that she really has a crush on Karasuma. She even confessed that although she has much experience and excessive proudness in conquering men, she is confused about his attitude. Class E and Koro-sensei, who know of her crush, tried to set them up. However, Irina didn't manage to confess, as she was supposed to, but tells him a story about her first killing instead.
 * With Class E: Their 'bitch', known as 'bitch-sensei'. Also, Irina is their single-subject teacher, who teaches them English.
 * With Lovro: Irina was Lovro's disciple. However, Irina still can't turn down her master's order until now.

Trivia

 * Originally Class E called her "Bitch-neesan" but after accepting her as a teacher, they quickly changed to "Bitch-sensei", however, Irina seems to hate both of these nicknames equally and prefers to be called "Irina-sensei"