Since the main character is usually referred to as the protagonist, the title you're probably looking for is antagonist.
What is the name of the main character?
The less important character in a play is typically referred to as a supporting character or a minor character. Their role is to complement the main characters and help advance the plot, providing context or conflict but not driving the main storyline.
the main character's name is Auturo
The main character is Grady.
The main character's name is Corvo Attano.
The main character would be the protagonist.
The name of the main character of the book Doomwyte is Bisky, a small mouse.
The main character's real name is Laurence Barnes, but goes by the code name 'Prophet'.
The name of the main character in the books Phoebe writes is "Princess Cordelia."
The name of the main character in the "N.E.R.D.S." book series is Jackson Jones.
The main characters name is William Wallace.
There really is no name for that person. It's just a character that makes life miserable for the main character. She/he doesn't really have a name at all.