Cavematsu-san 2 / Matsuzou and Matsuyo

The prehistoric sextuplets return, partaking in dangerous sports. / Noticing their father acting strangely, the brothers discover that he is worried that there's not enough spark in his marriage. After embarrassing himself in front of his sons, Matsuzou considers a love potion from Dekapan, but is this really the best way to patch things up with the love of his life?