Haruhi Suzumiya (涼宮ハルヒ Suzumiya Haruhi) is the founding member of the SOS Brigade with the purpose of finding aliens, time travelers and espers. Although she doesn't know it, all the members of the SOS Brigade she recruits, besides Kyon, happen to fit into these groups (Yuki Nagato, Mikuru Asahina, and Itsuki Koizumi respectively). She is incredibly eccentric and anti-social, with no interest in "ordinary" humans. She also, unknown to her, has the god-like abilities to change, destroy, and reshape reality. It is said that if she were to become bored enough with the world, she could simply erase it and start a new one. After revealing themselves to Kyon, the trio of Yuki, Mikuru and Koizumi all state they were sent by their respective higher-ups to watch over her, and Koizumi specifically mentions they must keep her entertained so she doesn't become too bored.

Biography

When Haruhi was in sixth grade, she went to see a baseball game with her parents and was shocked by the sheer amount of people attending. After finding out that the large amount was only a small piece of the entire world, and realized that she was only a small part of it, Haruhi believed herself to be ordinary, and deduced that if there is someone out there with an interesting life that it should be her. This results in Haruhi's desire to find strange things.

In middle school, East Junior High, Haruhi becomes known for several things, such as putting talismans up around school, dating and often immediately dumping every guy who asks her out, and, most notably, drawing a huge graffiti mural on the field on the night of Tanabata. Kyon was actually the one who drew this under Haruhi's orders after he and Mikuru traveled back in time. Thanks to the dark, Haruhi could not make out his face, and so Kyon used the alias "John Smith" to further keep himself secret. "John Smith" implied to Haruhi that there were strange things out there and that there might be interesting people at North High, inspiring her to attend the school.

When Haruhi attends North High, she meets Kyon, the first person there to openly talk to her. She takes an interest in him because he reminds her of John Smith, and eventually drags him into creating her new club, the SOS Brigade. By seizing a room used by Yuki Nagato to use as their club room and abducting Mikuru Asahina and Itsuki Koizumi to join her club, Haruhi unknowingly drags the exact types of people she wants into her life.

When Haruhi sees Kyon wrestling with Mikuru over a computer mouse, she becomes jealous and creates an alternate reality (closed space) in which she and Kyon are the only inhabitants. This becomes a threat, as the new world would possibly replace the old world. By kissing her, using clues from Yuki and a future Mikuru, Kyon convinces Haruhi to bring the old world back.

Haruhi thus becomes a participant in many activities surrounding her that she does not understand: the SOS Brigade wins a competition by modifying a bat; a logo for the SOS Brigade that she creates awakens an ancient data lifeform; she causes time to loop over and over because she does not want summer to end; she confuses the fictional world with the real world while filming a movie, causing the movie's events to come true; Yuki must hack into a computer game in order to satisfy her desire to win it; the world is altered, creating an alternate version of her with no powers; a mysterious alien entity traps her and the SOS Brigade in a strange mansion; a Mikuru from eight days later appears behind her back; a new potential god is revealed as Kyon's friend Sasaki.

In her second year, Haruhi starts to accept new first-year recruits into her Brigade, but is picky about who enters; she kicks out who she wants and challenges those who have the guts to return to the brigade room. When Yuki mysteriously falls ill, Haruhi organizes the rest of the brigade to go rescue her.

In The Surprise of Haruhi Suzumiya, she shows a much more human and even motherly side when she cooks and makes remedies for the ailing Yuki. Her intuition skills also show that she possibly thinks/knows that Yuki does not have a simple cold.

Sumber: Haruhi wikia