少年花心不滥情
[shăo nián huā xīn bù làn qíng]
The username '少年花心不滥情' can be translated to 'A young womanizer who doesn't go too far.' The character '少年' means youth, '花心' indicates someone who is fond of love or flirts around a lot (often referring affectionately), and '不滥情' implies self-control or moderation in romantic matters.