|Body Switching Spell|
Nina is Zero and Zero is Nina?!
The unnamed body switching spell is a spell used by Nanase Akatsuki that allows two people to switch bodies.
In order for the spell to function, Nanase attaches a seal to someone, and whoever removes the seal from that person will switch bodies with them.
The spell is broken with a Magical Release spell, though it can also be broken through a deep, personal connection between the two people under the spell.
Nanase uses this technique on Nina Yamada and Zero as leverage to take Nina, and thus the Crystal Pearl away in return for ending the spell. Nanase uses the wrong seal to break the spell, and so Zero and Nina are forced to break it themselves by getting close to and thinking deeply about one another.