Lyric discussion by littleshadow 

fallen might have it perfect... i think "key" might be "keys", "inside to a fantasy" perhaps. And, while the other interpretations are soo sweet, I think it's about a fan she thinks might be stalking her.

second thought, "key" is probably right.

as per fallen1617:

first three lines = fan staring at her/the band for too long during the opening act, from against the wall, "in the shadows" next line = wondering if he is dangerously obsessed next line = common self-defense tactic of using a key in one's fist as a weapon to strike an attacker lines 8-9 = fan moves up near the front of the stage for the performance, where he is struck with someone's camera on the brow, also where she stage dives. final lines = pondering/communicating with his inner world

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