蒲公英的约定原谅我不能忘
[pú gōng yīng de yuē dìng yuán liàng wŏ bù néng wàng]
Comes from a popular song titled 'Promise Of Love' where dandelion symbolizes dispersion and distance. This username conveys missing old acquaintances or loved ones and feels sorry because one can never forget those promises made long time ago under similar situations depicted in this song.