Jun Honganji (本願寺 純 Honganji Jun) is the trouble-hating Police HQ Chief. A man who is very into fortune telling and feng shui, he is seen wearing different ties on different days that matches his lucky color for the day. Because Shinnosuke tends to slack off, he assigns Kiriko to watch over him. He also has a very peculiar speech pattern. He later becomes the first user of the Mass Produced Mach Driver, transforming into a Production Model Mach, which he refers to as "Kamen Rider Jun" (仮面ライダー 純 Kamen Raidā Jun).
In episode 25, it was revealed that he already knew of Krim Steinbelt, having the two being old colleagues as well as Shinnosuke's identity as Drive and secretly supporting them by founding the Special Investigation Unit. Eventually, he even purposely exposed Shinnosuke and Go Shijima (Kamen Rider Mach)'s identity to the worldwide under the assumption that it would come in handy. Honganji was also a colleague and friend of Shinnosuke's late father, Eisuke Tomari.
During the period of time where Shinnosuke was dead due to Freeze, Mitsuhide Nira was desperate for Jun to work with the police force to select a new Kamen Rider. In turn, Jun snapped back at Nira, explaining that being a Kamen Rider requires more than just physical strength and intelligence. He and Krim had searched the entire police force for the right candidate in the form of Shinnosuke, and Jun states that Shinnosuke cannot be replaced by anyone else as Drive. Who Claimed the Life of Shinnosuke Tomari?
After the elimination of the Roidmude threat, Jun became the deputy commissioner of the Tokyo Metropolitan Police Department. Who Will You Entrust the Future to, My Friend?
Chou Movie War Genesis
un later appeared enforcing Mach, Chaser and Specter against a revived Heart, Brain and Medic Roidmudes, and Da Vinci Gamma as Kamen Rider Jun. Unfortunately, as his rider form is very weak, he was easily overpowered by an attack from the Da Vinci Gamma, knocking him out and killing him. His allies bring his body back to the Daitenku Temple to mourn his death. However, much to everyone's surprise and utter shock, Jun miraculously reawakened. He explained that while in the void connecting the afterlife to the mortal world, he met a mysterious being with whom he had a chat with. He was not permitted to enter the afterlife yet, because his allies in the mortal world still needed him, hence he was forced back into the mortal world, reviving him. Too weak to go outside helping his allies against Da Vinci's army, Jun remain cautious to find a safer place to defend himself.
Later, Jun attended the wedding of Shinnosuke and Kiriko along with the rest of the former Special Investigation Unit as well as the Mysterious Phenomenon Institute team.