你笑着说他只是朋友
[nĭ xiào zhe shuō tā zhĭ shì péng yŏu]
Means that when people mention this specific man/woman whom you know, you say smilingly 'He/She is only my friend.' This could either show indifference or cover up true feelings behind the scene. Such a nickname might express the complicated emotion toward a relationship between both sexes.