You're not a Monster

Kira is a normal teenager. That was forced into a killing game. And lived on the streets since she was 6. Who had a criminal record. And she lived with a gang of misfits and only had one person in the entire world. And she is a diagnosed psychopath-
Okay okay, she isn't normal at all. But above all those things that don't make her normal, one takes the cake. She is a Shifter, someone who turns into a giant four nights each month. The best part? Nobody knows. Not even her closest friend, Kokichi Oma. What happens when she runs into the poor boy on the verge of a transformation, and is found out? How will everyone react if they find out?
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Although this story is set in the killing game, no killings happen and Monokuma doesn't show up either. The game is referenced, but never put in motion.
Also, TW for violence, swearing (Kira is a potty mouth), mentions of death, mentions of injury, fear.