* TeasingCreator: In the writer's Q&A from the first volume, the writer gets away with spilling a future plot point by wording it as a SuspiciouslySpecificDenial.
-->'''Q:''' Where's Kyubey?
-->'''A:''' Huh? [[spoiler: [[LaserGuidedAmnesia What is this "Kyubey" again...?]]]]
-->'''Editor:''' Hey...wait...don't go giving away spoilers, please...
* WhatCouldHaveBeen: The author's notes in the final volume reveals that Mirai's magic was originally going to be "stealth" and Yuuri was initially named "Lamia".