Fu is a hybrid of two completely different species, a rare occurrence especially with a species as powerful as a demon. This mixed blood wasn't a mere coincidence since her father, Mori Raya, had a not so small obsession with hybrid children.

The man using any means possible to get a hybrid child, including participating in the dark auctions and buying them off the streets. Fu is considered Mori's greatest creation since she was the only hybrid child that has his blood and survived. Fu had become numb to all the siblings that come and go from the 13 story building, she hated how cruel her father was though not directly at her.

Fu went to Sena to get away from her father, his constant overbearing nature was suffocating and Fu wanted to save her siblings that resided on that 13th floor and she wanted to crush her father's company down. Fu bought a Sena admission letter from one of those stragglers on the street, and with that ticket she'll be attending Sena.