Callum Browne is a another way of saying 'Your Mum is in my sex dungeon.' Many people use it nowadays. For example Lebron James uses it. This is the phrase he is commonly known for. However, for Asians, Callum Browne is used for the word "I am having an orgasim." For White people Callum Browne means, I did your sister.
"Hey do you know Callum Browne?" Said Lebron James
"Callum Browne, Callum Browne," Said the Asian having Sex
"Hey I Callum Browne," Said the Guy
"I don't have a sister," said the Asian
"You will soon