Cause you never know when it all could be over tomorrow, so I keep conjuring
Since he could die any day and “tomorrow” is not always guaranteed he has to keep “conjuring” material. The use of word brings up two images:
Conjuring magic, which goes with the line right after, “sometimes I wonder where these thoughts spawn from”.
Conjuring a demon, which is bringing forth an evil spirit, which would explain why the next 2 bars are in a demonic voice.
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