少年薄唇亦绝情
[shăo nián bó chún yì jué qíng]
The phrase evokes an image of a young man with thin lips, signifying that he may be indifferent or heartless, highlighting the aloofness and unemotional nature in some youthful figures, which might imply that despite looking young and innocent, this person has gone through things that make him cold.