Osomatsu-kun S01 E48 Even the Sextuplets Become Good Boys at a Zen Temple!

"You're seeing way more than double! Try sextuple!"

After their dad decides it's time for them to learn some manners, the sextuplets are sent off to do zen training at Monk Iyami's temple, but get into trouble there too. When a mysterious drifter visits, the boys' mischief-making is put to the test.