You don't know what had happened for this to start, but it was terrible.

Your friends were disappearing, almsot day by day. And almost every night, you'd hear a new growl echo throughout the hallways in the facility...

Though, one time, you had accidentally ran into one of the twisted ones. You got hurt, and unfortunately, got some ichor into your wound. (That's how I imagine they'd turn twisted-)

Now, you were a blood-thirsty, corrupted version of yourself, roaming the halls as growls and hisses escaped your lips. All you could think was kill and hurt...