白衣少年浅浅笑黑衣少女媚如猫
[bái yī shăo nián qiăn qiăn xiào hēi yī shăo nǚ mèi rú māo]
'A young man in white smiled gently, while a girl in black looked bewitching like a cat.' It describes two contrasting characters and their personalities through color-coded imagery - innocent boyish charm vs enigmatic feminine grace.