Among Fuji, Matsushima, Sakura, and Momoki, "who's your favorite?" Yamada, who happened to be at a class reunion of these four members of the "Fruitful year," is faced with the ultimate choice! In addition to that class reunion, the Astro Brothers get girlfriends and the usual four go to the zoo. But, in contrast to such heartwarming stories, we also get a glimpse into the shady side of police box Chief Igasaki in a volume 19 that shows no signs of slowing down!