The “hmm” pyramid

When you sneak up on someone, and goose them with your finger into their butt, and say to them “hmmm hmmm hmm”!

I had a dream you snuck up and goosed me! All the while, you were kept muttering “hmm hmm hmm”! It is a real enigma, like the great pyramids. It made me think, he got me the “hmm” pyramid.