She wanted to live onshore and find love so bad that she made a "deal" with a "devil" and "sells" her beautiful voice, or "soul" so to speak.

她想到岸上生活，并渴望寻找真爱，于是她和一个“魔鬼”做了一笔“交易”，“出卖”了自己美妙的声音，或者干脆说就是“灵魂”。