海誓商盟
[hăi shì shāng méng]
This nickname blends a pun on '山盟海誓 (oaths sworn by mountains and seas, referring to eternal vows of love)' and business associations ('商盟'). It humorously indicates someone whose promises of loyalty and fidelity may have ulterior motives, possibly suggesting a more opportunistic or mercantile outlook towards commitments.