Life, Trauma/ Loss
After suffering the experiments on her and her baby Lillian transforms into a monster and escapes the lab.
The baby didn’t make it due to the effect of experiment but was kept intact by shear willpower, so he was taken from her womb to be further experimented on (baby was supposedly dead but was brought back by unholy means) this knowledge doesn’t go well with Lillian and with the effect of the experiment she went mad, transformed into the monster and escaped the Gray Fortress.