I've generally not seen ANY Black/Chinese relationships of any variety M/F M/M F/F F/M. Not even in the melting pot of the UK, thus I don't think there is. I have however heard this.
When TCG's cousin bought home somebody my uncle's severely disagreed with not because of his skin colour of anything but because he was a freaking rich bum. You know the kind, the kind who is rich but only because of daddy. Btw I have no problem with wealth if you have made it decently, (unlike rentierism) but daddy wealth I hate to an extreme.
Anyway it was kind of like this scene out of the classic German film Festen
It sort of literally means finger bending one way, traitor to your own kind. Sorta.
There are also comparisoms you can draw from the distasteful Lou Jing incident.