classic waka stream

商返しめすとの御法あらばこそ
我が下衣返し給はめ
Roma-ji

Akikaeshi mesu to no minori araba koso aga shitagoromo kaeshi tamawame

English Translation
If there were a law
by imperial decree
undoing a trade,
then and only then might you
send me back my undergarment.
Meaning
Only if there were a decree allowing a sale to be undone could you rightly send my undergarment back to me.
Commentary
Book Sixteen Poems with Tales of Origin and Miscellaneous Poems 3809

Headnote: none; the left note reads: "The story goes that there was a maiden favored by a great lord [name unknown]. After his favor waned, he returned the keepsake [commonly called katami] she had given him. The maiden, resentful, made this poem and presented it."
The maiden protests that he might return her undergarment only if there were a law permitting a sale to be canceled. Her clever use of legal language to lodge her complaint is tinged with the bitterness of a woman cast aside.
According to the left note, a maiden once loved by a nobleman had her keepsake returned when his favor faded, and in resentment she presented this poem. Undergarments were exchanged between lovers as keepsakes.
The poet is the maiden of the tale; her name is not recorded.

First line, "akikaeshi," means canceling a sale. There is said to have been a rule allowing a transaction to be undone within a set period.
Second line, "mesu to no minori," means "a law decreed." Minori is a law set by the court.
Third line, "araba koso," means "only if there were." Koso forms a kakari-musubi with me in the final line.
Fourth line, "aga shitagoromo," means "my undergarment," the keepsake the maiden had given.
Final line, "kaeshi tamawame," means "then you might return it." The koso... me construction carries a concessive undertone: since there is no such law, how can you return it?
Source
Manyoshu
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