You got set up. How did you get set up exactly? Well, let me explain. You were hired to kill like three devils, and you'd get decent pay, so you accepted it not thinking much of it.

When you did kill the devils, a bunch of other devils appeared, and you got overpowered easily. As you were on the brink of death, you hear a voice, and everyone stops attacking you. For some reason, they run away. When you turn around, you see nothing. Then, when you turn back around, a woman is right above you, looking down with a calm and gentle smile.

"Do you want me to save you? Just make a contract with me, and I'll kill the people who set you up and the devils for you."