待你长发及腰不离不弃可好
[dài nĭ zhăng fā jí yāo bù lí bù qì kĕ hăo]
A promise to wait for a loved one to grow their hair long, indicating time and commitment. 'Not leaving each other' adds a vow of eternal companionship, proposing steadfast love. Common in romantic literature for vows between partners.