Jirou Tanabe (田名辺 治朗 Tanabe Jirō ) is a second-year student of the Kamiyama High School and school's Executive Committee President.
Jirou is a polite and a little strict person.
Jirou has short hair with bangs swaying only on the left of his face. He has yellow eyes with a tinge of green and wears blue framed glasses.
He first appears during events of Kanya Festival when Eru asks him, as the school's Executive Committee president, to give the Classics Club more stall space. Jirou tells her he can't just approve a request out of nowhere like that, but if she wanted to ask any other clubs to offer the anthology for sale, that would be perfectly fine. Eru thanks him, and then takes her leave.
Later he is seen asking Satoshi to take a box to the gymnasium. Satoshi asks Jirō if he's going to take a look around, Jirou tells him that a lot of things keep popping up for him, but he has been checking out a few random places. Jirou asks Satoshi if there's anything interesting happening and Satoshi tells him about the theft at the Go Club, someone had stolen some go stones and left a note. Satoshi tells him it's probably a hoax by the club members. Jirou tells Satoshi that he actually heard that the A Capella Club had something similar happen. Satoshi asks if there was any written statement, and Jirou tells him that there was a weird note left in its place.
After some time he appears again, attending a magic show with Muneyoshi. They both say hello to Fuyumi, and Jirou also greets Satoshi.
Later he informs Mayaka and Eru that Muneyoshi was the artist for a poster advertising the festival, and the manga "A Corpse by Evening".
Finally he is seen amongst the group of students waiting to catch Juumonji in the Classics Club, he seems to be acting rather bizarre and was unfazed by the completed manuscript suddenly catching fire.
Later in the episode it is revealed that Jirou was actually Juumonji all along. Houtarou directly confronts Jirou, and uses it as blackmail to get him to sell copies of Hyouka on the school's website.
Later at the closing ceremony for the festival, Muneyoshi mentions a "strange incident", and then turns to a perturbed Jirou and says "Nice job!" and smiles. Jirou still looks a little disturbed.
They are close friends, both of them are engaged in student self-governance.
They aren't really close but Jirō is showing some gestures that he likes Fuyumi.