classic waka stream

Together we left
the great palace mountain, yet
you will not show me
where you go in to—you are
the moon of the sixteenth night

Meaning
We came out from the palace together, and still you will not show me where you go in—you, moon of the sixteenth night.
Commentary
Part One: Suetsumuhana

 Genji's grief for Yugao had not lifted, and he was looking for a woman he could be easy with. From Taifu no Myobu, his nurse's daughter, he heard of a daughter of the late Prince Hitachi who lived on in a ruined house, playing her koto, and out of curiosity he went there in secret. But To no Chujo, suspicious of his movements, had followed him. Revealing himself, To no Chujo spoke this poem as a reproach. Genji answered, the two of them laughed, and afterward they wrote to the lady almost in competition.

 "Ouchiyama" means the palace, and by way of the mountain in the name it leads into "going in" and "the moon." The moon of the sixteenth night is one that hesitates before rising, and it stands for Genji, who will not say where he is going. The plain fact—that they left together and one of them disappeared—is laid directly onto the movement of the moon. It is banter between close friends, and yet the form of the poem is kept exactly.
Author
Murasaki Shikibu
Source
Genji Monogatari
Other