she was walking down the street casually letting one go when with a massive burp her anus spewed forth a massive blob of bum custard
similar to [fanny batter] it is a product of the anus usually (but not exclusively) derived from a mixture of lubricant, sex wee and faeces
"she was walking down the street casually letting one go when with a massive burp her anus spewed forth a massive blob of bum custard" What is the definition of "bum custard"?