Hitogokoro asasawamizu no nezeri koso koru bakari ni mo tsumamahoshikere - Kinyo Wakashu(English Translation & Meaning)

人心あさ沢水の根芹こそ
懲るばかりにもつままほしけれ

Roma-ji: Hitogokoro asasawamizu no nezeri koso koru bakari ni mo tsumamahoshikere
English Translation: Shallow is your heart,
like Asasawa's waters
where the rooted parsley grows—
so much would I pluck and pinch
till at last you learn your lesson
Meaning: How shallow your heart is, like the waters of Asasawa where rooted parsley grows; I would pluck at it and pinch it until you learned your lesson.
Commentary: Book Eight Love Poems II 432

As one plucks the rooted parsley growing in the waters of Asasawa, the poet would like to pinch that shallow heart until its owner learns a lesson. Resentment toward a heartless lover is expressed with wit, weaving in Asasawa, a famous place at Sumiyoshi, and its rooted parsley.
The latter part of this book gathers witty love poems layered with pivot words, as from poem 494 on, and this poem shares their playful spirit.

First line, 'hitogokoro', means the other's heart, leading into asa, shallow, in the second line.
Second line, 'asasawamizu no', is a pivot word in which asa means both shallow of heart and Asasawa, a famous place at Sumiyoshi in Settsu, left in kana.
Third line, 'nezeri koso', means the rooted parsley, the particle koso answered by hoshikere in the final line.
Fourth line, 'koru bakari ni mo', means even until you are sorry, that is, until the other learns a lesson.
Final line, 'tsumamahoshikere', seems to be a pivot word in which tsuma means both to pick the parsley and to pinch with the fingertips, left in kana. It closes with mahoshikere, the perfective form of the wishing mahoshi, in answer to koso in the third line.
Source: Kinyo Wakashu
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