This is a fantasy based on reality.
Gokukoku no Brynhildr Opening
I won't let anyone touch Haru.In other words, not twelve assassins, but eleven and one protector.
Last time, you swore that you would never forget me. I’ll tell you the story of how you and I met. From the very beginning.
“‘You seem very girlish tonight’. Akio-san said that to me. Very girlish…Just what does that mean?”
"Girls are…In the end, girls are all like Rose Brides."