'Rob Lam' is the ancient tradition of a village located on the border of Vietnam and China, Shlam village.
It is a sex position that involves a woman with a large buttocks greasing her naked behind and rubbing it all over the also naked reclined male. The woman then sits motionless on the man's face, whilst he masturbates for up to and over an hour.
This mysterious tradition dates back thousands of years.
'Did you seen that documentry on Shlam village'
'Yeah, that Rob Lam thing was really strange'
'Mhmmm.... Dat ass doe'