一个以为不会走一个以为会挽留
[yī gè yĭ wéi bù huì zŏu yī gè yĭ wéi huì wăn liú]
This name expresses the bittersweet emotion in a farewell scenario. One person never thought the other would leave, and one assumed there would be an attempt to stop the departure. It's like the two sides were on completely different wavelengths, revealing feelings of helplessness and regret over the end of some relationships.