Kyon is the main protagonist and narrator of the Haruhi Suzumiya series, a popular series of light novels first published in Japan in 2003 whose immediate success had since caused the franchise to expand into a variety of other media such as an anime series and multiple video games. The name “Kyon” is not his real name but a nickname given to him by his aunt and spread by his little sister. Neither his name or his sister's has been revealed to this day, however it is hinted that his name has a majestic quality to it, that incidentally didn't seem to fit him.
Seated right in front of Haruhi
's desk (even after the seatings had been rearranged by random drafts), Kyon is the only classmate to engage Haruhi multiple times (possibly possessed by some demon as he jokingly infers). Their second conversation in which he points out the pattern of Haruhi's ever-changing hair style marks, in his own words, an important trigger for her growing fondness of Kyon, although even he isn't fully aware of the implications when Haruhi asks him, if they had met before (see section: John Smith). In one of their regular chit-chats during breaks, he inadvertently gives Haruhi the idea to form her own club and is subsequently forced to help her build the SOS Brigade.
As the central protagonist and narrator of the events surrounding Haruhi Suzumiya and her SOS Brigade, he is often dragged into her ridiculous schemes against his will and his retelling is often spiced up with sarcastic commentary. While his grades are merely average, partially because he doesn't find the time to study due to Haruhi's plethora of planned activities, he is very observant of his surroundings, especially when Haruhi or the other Brigade members are involved. He also displays remarkable general knowledge during his narration, often referencing highly complex notions of science and literature to draw comparisons.
As the first member to be forcefully recruited for the SOS Brigade, Kyon often refers to himself as the voice of reason, as he is the sole person Haruhi would possibly listen to if someone was to object to her ideas. That is not to say that anyone else would ever object, as Itsuki is generally inclined to have anything Haruhi's ways in order to maintain the world's status quo, while Yuki, content observing any possible outcome, is indifferent and Mikuru is mostly oblivious to the consequences. Although he often expresses a certain melancholy whenever Haruhi would come up with another club activity, Kyon admits to himself on several occasions that his life is ultimately more exciting and more fun which is best displayed when he opts to revert the state of reality when the world had been changed over night in The Vanishment of Haruhi Suzumiya.
Being the only 'regular' human of the SOS Brigade, Kyon's presence is still a big mystery to the other three factions observing Haruhi since, while she had explicitly wished for aliens, time travelers and espers to join her, there is no immediate (paradox-free) explanation for his appearance. This fact makes Kyon arguably the most important person to Haruhi which first becomes apparent at the end of the first novel, when Haruhi's discontent with the current state of the world reaches a point where she is willing to reshape reality, save for him.
John SmithThe name 'John Smith' is a pseudonym Kyon used during the important “Bamboo Leaf Rhapsody” episode in the third novel. Following her superior's orders, Mikuru takes Kyon back in time to the Tanabata festival three years prior to the story's timeline, cited as a critical event in Haruhi's existence. He uses the name in order to conceal his identity from the young Haruhi when he is forced to help her draw a gigantic symbol onto the school's playing field. This event is first referenced when Haruhi asks Kyon, if they had met before which Kyon denies at that point. The name also gains critical importance during The Vanishment of Haruhi Suzumiya and Kyon points out that mentioning that name to Haruhi was his ace in the hole in case something was to happen.