Robin and Nightwing are both portrayed by Dick Grayson. Grayson was a child when Bruce Wayne took him under his wing seeing as they both lost their parents similarly. Forming the duo “Batman & Robin”.
Robin is shot (in the shoulder) by The Joker at the age of 17, scaring Batman into retirement. Grayson comes to a realization that he no longer needs to live under the Batmans wing anymore. He then relocates to NY forming the Teen Titans. Batman upset tells Grayson he has to drop the Robin moniker if they are no longer partners. Dick Grayson gets the name “Nightwing” from Superman.
This line pertains to only two of Dick Grayson’s three alias’s (Shortly portraying Batman when Bruce Wayne was thought to be dead).
I’m fighting to do what i love and if i catch you doing wrong its gonna be a problem.
This line could also mean if you’re content with being a sidekick (follower) i’ll be the leader.