C141 You Know Each Other

Gu Yuan thought to himself. If Nan Xueer wasn't wrong, it should be a song that the two of them had cooperated with each other before.

That song was called sorry.

It was a song composed by Nan Xueer, a work that Gu Yuan filled in words with.

The background of this song was the first time the two had quarreled when they were in love. However, that was already in the past