愿陪你上穷碧落下黄泉
[yuàn péi nĭ shàng qióng bì luò xià huáng quán]
'Wish to accompany you to the farthest heaven above or deepest hell beneath' indicates a willingness to go through any journey, whether in paradise or purgatory, together. It shows unconditional loyalty and commitment regardless of conditions—reflecting a very dramatic yet deeply touching promise found commonly within romance contexts in China.