Literally translates to "King Oedipus."
A greek tragedy from the greats. The story of a king whose fate is to kill his father and marry his mother.
Yes, those are true, but Oedipus Rex is more widely known as the controversial passage of famous Doors song The End.
The killer awoke before dawn, he put his boots on.
He took a face from the ancient gallery and he walked on down the hall.
First he went into the room where his sister lived, and then he paid a visit to his brother, and then he walked on down the hall.
And he came to a door, and he looked inside. Father? Yes, son? I want to kill you. Mother? I want to F*CK YOU!!!
A euphemism for motherfucker, along the lines of sugar honey iced tea, since Oedipus literally was a mother fucker (and a father killer).