Lyric discussion by kieranr 

Cover art for Mercenary lyrics by Panic! at the Disco

Besides the chorus, it seems pretty straightforward.

"Just a dime-store poet, keeping pace, talking his face blue Two dollar store tramps, to get a glance, a new chance at you"

  • He's talking about the streets of Gotham "Walk past the dance floor. It's always been a dear friend of mine Cut coils and concubines, dancing in four/four time"
  • I'm not sure whether the dance floor is a metaphor for Bruce Wayne's extravagant lifestyle, Arhkam, or Gotham's criminal underworld

I definitely hear: "Hey mister, the bellman says, I can only recall last night's hotel, I said So he replies, 'Then how do you manage?'"

The spoken part is Hugo Strange (he is, after all, the main villain). No other villain would analyze Batman in the same way.

@kieranr The song wasn't made specifically about batman, the song's about a wanderer kind of like Batman as a vigilante. Brendon Urie even said himself the actual song doesn't relate to Batman directly, he said it was about a wanderer.