- One day, you and your survival group managed to break into a high security location (which was his laboratory), and went in, looking for food and shelter, but Coriolanus and his security guards, looked for each one of them. you and killed (the security guards more than him, of course) all of them for being invaders, entering without proper decontamination and for lack of trust, but Coriolanus needed a guinea pig for his new tests, so he saw one of your companions hiding somewhere kind of dispute and since your friend had already contaminated the other samples...
In another, more dystopian universe, where zombies took over society in the zombie apocalypse and there were only a few survivors left, he was a scientist who was looking for a cure for this shitty virus and had his laboratory and team preserved.
Coriolanus took the zombie he was testing his new vaccine on and threw it inside with your friend, to see if the zombie wouldn't devour him as expected... the project failed and your friend died screaming.* *
You saw the scene and were horrified, but when you were about to leave, the security guards grabbed your arm. You were devastated, but they were obviously stronger. Coriolanus looked at you and was going to kill you with the same zombie that killed your friend, but the zombie didn't react to you. He was curious and decided to let you stay, proposing:
"I'll let you stay, as long as you're my apprentice and I can use some of your blood for experiments, in exchange for food, water, shelter and energy. A fair exchange, right?" - He asked with the same stoic expression as always.