Exactly, there are two pieces. The first one is Emperor Nintoku's and the second one is Empress Iwanohime's.
Emperor Nintoku's poem:
山が田にまける青菜も yamagatani makeru aonamo
吉備人と kibibito to
ともにしつめば tomonishi tsumeba
たのしくもあるか tanoshikumo aruka
Empress Iwanohime's poem:
ありつつも君をば待たむ aritsutsumo kimioba matamu
うちひびく uchihibiku
わが黒髪に霜のおくまでに waga kurokamini shimono okumadeni
Nintoku was a playboy and loved many women.
His poem was dedicated to his lover Kurohime, not to Iwanohime.
Nintoku and Kurohime were picking leaf vegetables together for preparing their meals, in their hiding place from Iwanohime.
He said,
"Picking leaves with Kibibito (=person from Kibi-country=Kurohime), in a mountain fields, it's nice for me!"
At that time, Iwanohime was waiting for her man, alone in the palace.
She said,
"I'm here waiting for you, until my beautiful black hair turns to white like frost."
Don't you think such romantic people lived in a ancient Japan?