This is so AU, I don't even know.
The gist (all of which is subject to change with upcoming chapters and is INCREDIBLY roughly sketched out right now):
( World & Timeline Info )
( Lenalee Lee )
The short version: After Allen was broken out, and following several encounters with the Cardinal, Lenalee became an Apocryphos due to her overpowering desire to protect him from the Apocryphos.
The gist (all of which is subject to change with upcoming chapters and is INCREDIBLY roughly sketched out right now):
( World & Timeline Info )
( Lenalee Lee )
The short version: After Allen was broken out, and following several encounters with the Cardinal, Lenalee became an Apocryphos due to her overpowering desire to protect him from the Apocryphos.