少年不复存在一个词叫变质少女不再回来两个字念变质
[shăo nián bù fù cún zài yī gè cí jiào biàn zhì shăo nǚ bù zài huí lái liăng gè zì niàn biàn zhì]
It narrates that like the youth, things have deteriorated beyond recognition ('变质'). 'No longer in existence' implies both a young man and woman cannot return to their youthful selves due to irreversible changes, evoking feelings of loss and nostalgia.