Irina

(Some of the characters mentioned haven't arrived at sornieth yet! there are plans for it, though!)

PHOENIX's female combatant who specializes in assassination. Contrary to her delicate appearance, she has a dangerous side in which she frequently says "Please die". Born in a war-torn country, she has a history of her friends and family dying in war. Therefore, Irina believes that if she robs power and wealth from major countries, the world would be impartial and peaceful, allowing her to aim for her "big dream" of world equality. She seems to seek success in her career in order to quickly make her big dream come true.

Irina acts in a very nonchalant, deadpan, robotic-like manner, but her words and actions can be very expressive and blunt. She refers to herself in third person.

She doesn't seem too fond of others being friendly with her; examples being when she threatens to "kill" her cooperative partner Anthony, shrugging off Maria when she touches her, or when she smacks Benedict on the head when he asks her for a handshake.

Etymology
Spessivtseva (スペシフツェワ) has no meaning on its own, but it is the surname of the Russian ballerina Olga Spessivtseva (Ольга Алекса́ндровна Спеси́вцева).
Irina (イリーナ) is a common Russian name with Greek origins. It is derived from Eirene (Εἰρήνη), an ancient Greek goddess who is the personification of peace.

Although not explicitly stated, there are many implications that Irina is from Russia. Her name is of Russian origin, and in the 2nd stage play, it is stated that Irina had met Maria in a Russian facility. There is also the common occurrence that most Russian characters in Japanese media are designed with silver hair.
She has been trained and disciplined as an assassin since she was a child.