It is used at the beginning and or sometimes the end of a sentence, to draw a fellows attention, towards a female for which your feelings are unpleasant.
He's a Belgian Motherfucker Serie A's top scorer
Romelu Lakaka u dont wanna mess with
'Cuz then hell score and squeeze ur tit
He's the no.9 nigg-ahh
Who's feared by the whole of Asia
That is Romeluuu Lakakaaa