告别单纯烟是爱人
[gào bié dān chún yān shì ài rén]
'Farewell to innocence: smoke is the lover' expresses farewell to an innocent or pure state. Smoking here might be used as a sign of growing up, becoming more worldly or indulging oneself after losing the simplicity. Or the 'smoke' might be used metaphorically for things like memory or love, something abstract or ephemeral, which is close but can't touch, much like the relationship of lovers.