Paramore on Fallon, Ba Da Da Da Da, or Paramore vs. Apollo Up! Pt. 2

Local arena-rockers Paramore played their song "Brick by Boring Brick" on Fallon last night, and the Internet provides the video proof above. I have no idea what this song is about, but I think the castle represents childhood and innocence, or maybe it's a literal castle surrounded by a moat filled with dragon tears. Like I said, I don't know. What I do know is that there's this part that goes, "Ba da da da da da," approximately, and that it reminds me of something.