|Height||170 cm (5'7")|
|Occupation||Student (grade 10-11)|
|Introduced In||The Melancholy of Haruhi Suzumiya|
|Last Appearance||The Surprise of Haruhi Suzumiya|
|Voiced by||Minoru Shiraishi (JP)|
Sam Riegel (EN)
Boris Alexeev (RU)
Taniguchi is comically lecherous; he gives a 'score' of attractiveness to each first-year girl based upon his tastes and preferences. He remembers the full names of everyone receiving an 'A' rank, with Ryoko Asakura receiving an AA+ and Yuki Nagato receiving an A-. In the manga he also ranks Haruhi Suzumiya as A+. Taniguchi however never actually pursues any of these girls (though he is implied to be the one who went out with Haruhi for the shortest amount of time she has ever dated: five minutes). As for Mikuru, her mere presence elicits an altered state of adoration for Taniguchi.
In the manga version Taniguchi is hinted to have had a much closer relationship with Haruhi during middle school. When Kyon questions her about her middle school activities in "The Melancholy of Haruhi Suzumiya III", she answers, "I don't know what you heard, but it was all from Taniguchi, right?" In addition, though Kyon still suspects Taniguchi of being the one to have dated her for five minutes, in the manga Taniguchi doesn't say anything that would suggest this is the case.
In The Sigh he attempts to hook up Kyon with Haruhi, by shooting down Kyon's first two choices of Mikuru and Yuki.
When Yuki Nagato alters the world, he loses this date, an event that is initially unexplained, but later it is revealed that the girl only agreed to go out with Taniguchi as part of a mission to observe Haruhi; since Nagato altered the world to leave Haruhi with no powers, she no longer had a reason to go out with him. This lack of plans for Christmas Eve is the first strange thing Kyon notices about the new world. Aside from suffering from an inexplicable cold, Taniguchi's personality remains intact in the new world, and because Yuki was unable to alter anything beyond one year before, he still remembers Haruhi, and indirectly helps Kyon find her. When Yuki turns the world back to normal, Taniguchi regains his date and good health.
In The Intrigues of Haruhi Suzumiya, Taniguchi is "dumped" by his date, who tells him she "made a mistake". He lets her keep his watch. (She is later revealed to be Kuyou Suou.) After the breakup Taniguchi falls into a state of depression. He tells Kyon that he envies him (because he believes Kyon is dating Haruhi).
In The Surprise he has a chance encounter with Kuyou. She tries to return his watch but he refuses. Afterward he tells Kyon a little about their relationship. Kuyou later tells Kyon she had mistaken Taniguchi for him, and broke up with him when she realized her mistake.
The Disappearance of Nagato Yuki-chan
In The Disappearance of Nagato Yuki-chan, Taniguchi injured himself while trying (and failing) to impress the girls at Kouyouen. Kuyou Suou noticed him and dragged him to the infirmary. Afterward they began dating.