Kenji Miyazawa vs. Young Men's Association

Kenji Miyazawa vs. Young Men's Association is a battle fought between Armed Detective Agency member Kenji Miyazawa against a gang during an investigative work requested by the police for the Agency.

It happened somewhere on the streets Yokohama where Kenji and Atsushi Nakajima are cornered by the gang after being briefly and straightforwardly interrogated by Kenji.

Prologue
After Atsushi and Kyōka Izumi recuperate in the Agency after the confrontation against Ryunosuke Akutagawa at sea, officer Minoura and his subordinate hand a police request to the Agency regarding a recent vehicle explosion. Doppo Kunikida assigns the task to Atsushi, with Kenji later taking on the request with him. At the site of the exploded car that was left plunged to a building, Atsushi is overwhelmed at the sight, while Kenji suggests that they look for some leads.

With Kenji's recognition throughout the shopping district, they acquire a tip on the recent purchase and use of nitrogen fertilizer by a certain party. Kenji then surmises that a "young men's association" (referring colloquially to a gang) might be responsible in the car explosion, so he and a reluctant Atsushi head to their base for questioning. Kenji frankly asks the gang whether they are responsible for the car explosion, which the gang denies. Kenji then leaves, firmly believing them despite Atsushi convincing him of their upfront lies.

Battle
On their way back, Kenji and Atsushi are blocked by the entire gang, who suspects that the detectives must have left immediately because they have most likely found evidence about their involvement in the recent car explosion. To their confusion and surprise, Kenji beamingly thanks them for coming all the way to confess their crime. He then asserts to Atsushi that sincere communication indeed leads to mutual understanding among people, which he claims has always worked in all his investigations. A gang member suddenly hits Kenji's head with a steel pipe, catching Atsushi off-guard.

As the gang slowly closes in on Atsushi, Kenji nonchalantly stands back up unfazed, assuring Atsushi that such things tend to happen especially back in his hometown. He then effortlessly lifts up an entire car and tosses it at the gang with his bare hands. Kenji later throws various other vehicles at the fleeing gangsters and casually swings a signpost he ripped off the ground at the gang. In the end, Kenji defeats the entire gang, while Atsushi discovers Kenji's monstrous strength.

Aftermath
With the gang defeated, Kenji and Atsushi stop by and eat at a nearby restaurant on the way back to the office. Later, Atsushi contacts Kunikida and panics that he cannot perform the same unorthodox way that Kenji works. Kunikida calms him down and praises him for realizing it himself, soon explaining how Kenji's ability works. He also informs Atsushi that Kenji's power only works on an empty stomach, as he ends up sleeping otherwise.

Manga and Anime Differences
A minor difference in the anime shows Kenji sitting on the pile of the defeated gang, while they are scattered around him on the ground in the manga.