你转身就会忘记的路人甲
[nĭ zhuăn shēn jiù huì wàng jì de lù rén jiă]
Translates as 'You'll Forget Me Once You Turn Away - Just a Walk-on Character'. This self-deprecating phrase reflects feelings of insignificance or transience in others' memories, possibly suggesting that the person feels unremarkable or unnoticed.