Honjo is first seen when Jiro breathlessy makes his way to the university which caught fire during the earthquake in Kanto in 1923. As the library caught fire, he is seen trying to rescue and save the books from burning in the fire. Honjo is a thin man, with a happy spirt, a love for airplanes like Jiro, and laughs at most things, including Jiro for daydreaming. But, Jiro and Honjo are also buisness partners and friends and they would do almost anything for each other.
Also, Honjo is also very smart and wise when it comes to designing aircrafts and he and Jiro bounce ideas and planes off of each other.