Todomatsu starts to work at a stylish cafe. His brothers try to disturb his fulfilling life. / Dekapan and Dayon enjoy a carefree travel together toward north.

Karamatsu ends up as Chibita's apprentice at his oden stand. Meanwhile, Jyushimatsu falls in love and his brothers try to help him achieve his romance.

Wanting to become the main protagonist of the franchise again, Iyami holds a bizarre kart race to determine who the protagonist of Osomatsu-san will be.

Noticing Matsuzou acting strangely, the siblings discover that he is worried that there's not enough spark in his marriage with Matsuyo. Feeling he should return to a more innocent time, the boys give Matsuzou a masterlcass in being a virgin, albeit with no success. Matsuzou inevitably resorts to getting a love potion from Dekapan, but ultimately decides against using it, managing to sort things out with Matsuyo by himself.

The brothers get rowdy while getting drunk at a restaurant. Unemployed office lady Totomi ends up taking a job at a strange establishment that offers some peculiar services. After being visited by a salesman, Matsuyo contemplates sending off one of her sons to a NEET correctional facility, asking Choromatsu to help her decide which one to send away.