你敢地老我就敢天荒你敢不离我就敢不弃
[nĭ găn dì lăo wŏ jiù găn tiān huāng nĭ găn bù lí wŏ jiù găn bù qì]
This username comes from the phrase 'If you dare to let time grow old, I dare to wait until the end of the earth; if you do not leave me, I will never abandon you'. It means a lifelong unwavering love.