So when I first saw Naruto seeing the scene where Kikashi uses his "1000 Years of Pain" on Naruto when he tried to get everyone's lunches when Kakashi isn't looking i thought this was just some joke made up in Naruto.
the other day watching A Lull in the Sea in Episode 15 I Saw Hikari chasing Ikari's son doing the same thing saying "kanchou kanchou" and telling Ikari he was going to give him "3 years of Pain". i also seems to remember seeing Ikari's son do it do someone
Both Hikari and Kikashi do mostly the same thing, they clasp their hands together with their index finger pointed out and poke their target in the butt
Now i am wondering where this poking someone in the butt originate from? Is A Lull in the Sea getting it from Naruto or is it from something else in Japanese culture