The Fujianese take male-male eroticism very seriously. Regardless of his social standing, each man bonds with another man of his own social class; the older one is known as the "sworn older brother" and the younger one is known as the "sworn younger brother".
If we carefully examine the differences between Min Nan and Min Dong and Min Bei, we can see that some of the similarities between Min Nan and Hakka are exactly the main content of this kind of differences.