The publisher announced in June that it would be relaunching its entire publishing line this September in an initiative referred to as 'The New 52'.
A Facebook campaign of 500 members was created to plan the protest, although only about 20 or so costumed fans actually turned up for the demonstration.
Foreign exchange student Laura Hornack, who organised the protest, said that she was unhappy with the drastic redesigns DC Comics had planned for her favourite characters.
"I understand that reboots happen," the 17-year-old told Newsarama. "I know that I'll have to wait and see with most of the books."
Fellow protestor Tara Strand said that she had initially felt 'outraged' about the DC Comics relaunch.
"I feel like the people who are now in charge of these characters do not understand how Harley Quinn works at all," she explained. "I don't feel like this relaunch can last, it just feels like corporate interests trying to make money."
She added: "I'm not mad anymore. It just feels like DC Comics is giving up on the diehard fans who have been around for years."
DC Comics director of public relations Brandy Phillips eventually greeted the demonstrators outside the event and presented them all with free T-shirts.
She said it was "fantastic" that the group were so enthusiastic about the DC Comics product and recognised that the protest was "in good fun".
The 'New 52' begins at the end of August with the launch of Justice League #1.
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