Whenever I see stories like this, I always remember Mirai Nikki and think that such situations should be handled like this:
MC: “You killed that dude?”
Her: “Yes?”
MC: “Because I told you to?”
Her: “Yes.”
MC: “Will you kill me?”
Her: “No, as long as you don’t cheat on me.”
MC: “Will you kill my friends even if I don’t ask you to?”
Her: “No, as long they are not girls.”
MC: “Alright, then we can date.”
The End