The poem at the top reads:

At night, hearing the sound of a big drum--

is it kagura-bayashi?

Now is the season for hibernating

It needs some explanation. Kagura-bayashi is an uncanny phenomenon, which we will examine in the next chapter. It is the sound of kagura dancing and music in the night, but when there is no performance of kagura anywhere nearby--or at least no human performance. It was thought that such mysterious music came from the playing of tanuki--a type of badger-dog and a notorious trickster. One attribute of tanuki was the male of the species possessed an enormous scrotum. And--ouch!--they would use this scrotum #as a drum# to produce their night-time music (kagura-bayashi or tanuki-bayashi). So the poem is likening the role of this man's organ with that of a tanuki's scrotum.

Now, compare this image with the previous one of Lady Yang and the Tang emperor (click on the thumbnail image below):