User blog comment:Zachc108/What does "sera" mean?/@comment-33028878-20180329044247

Well, "sirrah" is from a real title (IRL).

Wikipedia :

"Sirrah is an archaic term used to address inferiors, sometimes as an expression of contempt (but not as familiar). The term appears in several Shakespeare plays, such as Julius Caesar, Othello, and Antony and Cleopatra. It is related to "Sir", even though the social connotation of its use are opposed."