Character Profile: Itsuki Koizumi

Itsuki Koizumi is a transfer student in the same high school Haruhi Suzumiya and Kyon attend. How he came to the S.O.S Brigade was that Haruhi, out of a whim, figured that the club could use a "mysterious transfer student" to fill their membership. As a result, the ever-smiling Itsuki was dragged in as a member.

As stated before, Itsuki almost always seems to be smiling and not seeming to have a care for the world, even in the face of the moody Kyon. However, on one day, he did confided in a secret to Kyon, when they were not within Haruhi's earshot. It seems that Itsuki is an ESPer, one of the beings Haruhi is seeking to meet. He only came to realize his powers three years ago – which coincidentally was on the very day Haruhi realized that her life was not as unique as everyone else's. Now her occasional moodiness is inadvertently causing unusual events known as "closed spaces" – practically-invisible voids – to appear in the city, which then follow the appearance of shinjins, gigantic entities that represent Haruhi's frustrations, which then wreak the buildings within these closed spaces. If these closed spaces and the shinjins within them are not dealt with quickly, they have the ability to swallow up the entire earth and in effect, end all existence.

Itsuki is a member of a mysterious organization known as "The Agency", which believe that Haruhi possesses some form of god-like ability, and when her frustrations open the closed spaces, he, along with other ESPers, do battle with the shinjin created within, thereby collapsing the spaces. He even shows Kyon what he has to deal with in order to let him know that he is the key to help Haruhi maintain some form of emotional stability... or else the earth is doomed if he doesn't.