A man named bob...is indeed your uncle....but he is also a sex attacker....who has stolen several children from local primary schools....the term is a mix between "harry is your grandma" and "eddie is yow bitch mo-fucker".
Boy: Oh...hi there...are you ok? you look kinda ill...
Girls Father: You fucked my daughter!!!, omg WHAT THE FUCK?!!!
Boy: BOBS YOUR UNCLE dick face!
Girls Father: Oh mein GOT!!! im gonna go bustle in the hedgerow.