Any sentence that has to do with “ur mum” indicates that the person who said that is either homosexual or is seeking a sexual partner who is the same sex.
Oh I went to ur mums house last night, and I made out with a guy.
sexy bitch
gets all the bitties
milf
whore
Dam id bang ur mum, shes a baddie
Ur mum is a common insult used for no apparent reason. This also references to Yo Mama jokes. This humor is weird and sometimes unlikable.
Ur mum is fat.