In the second season the story continues exactly where it left off previously. Professor Itsuki's Fermentation Cellar and laboratory is ready for operation and with Sawaki Tadayasu's unique gift to see and communicate with microbes to help, Itsuki's motley group of students begin to process different fermented products like soy sauce and sake. (Source: ANN)

The majority of the Matsuno household is comprised of six identical siblings: self-centered leader Osomatsu, manly Karamatsu, voice of reason Choromatsu, cynical Ichimatsu, hyperactive Juushimatsu, and lovable Todomatsu. Despite each one of them being over the age of 20, they are incredibly lazy and have absolutely no motivation to get a job, choosing to live as NEETs instead. In the rare occurrence that they try to look for employment and are somehow able to land an interview, their unique personalities generally lead to their swift rejection. From trying to pick up girlfriends to finding the perfect job, the daily activities of the Matsuno brothers are never dull as they go on all sorts of crazy, and often downright bizarre, adventures. Though they desperately search for a way to improve their social standing, it won't be possible if they can't survive the various challenges that come with being sextuplets! [Written by MAL Rewrite]

Third season of Osomatsu-san.

From standing in the sun for hours to traveling miles away from home, gorgeous high school student Koizumi stops at nothing to fulfill her desire for ramen. But these previously solo trips soon change when Koizumi's classmate Yuu Oosawa develops an infatuation with her, and begins to join Koizumi uninvitedly on her adventures. As Yuu continues to be shocked by Koizumi's enormous appetite, she learns about the endless variety of ramen from, arguably, its greatest connoisseur ever! [Written by MAL Rewrite]