Well I didn't see the question originally but I wouldn't have wanted to answer it anyway because I have the feeling you aren't looking for an answer. You don't really want to know about God's character, and about Jesus' death on the cross. You want to show how witty you are and how stupid Christians are. And it frustrates me that you would use such an incompetent analogy, which just shows how little you understand. But I'll do my best to give you a simple answer.
The penalty for sin is death. Many countries and even US states have a death penalty for killing a fellow human. But sin against God is much more serious, and the penalty is death, physical and spiritual. The covenant God established with his people involved animal sacrifice to pay for their sins so that they could continue to be in right relationship with a holy God. But it didn't work - people continued to disobey and walk away. So God himself came to earth as a human to sacrifice himself as the punishment for all our sins. Only he could do it, because only he is holy enough to serve as the sacrifice. (When Jews sacrificed animals they had to be unblemished, because they represented purity which was taking the place of the punishment which we deserve.)
As for your lovely analogy, there really is no analogy that can accurately explain the relationship of the trinity, three persons in one God, because we don't have that in ourselves. We are one person in one person. Just like you can't imagine never having been born but always existing, because you were born, it's all you know. I realize you can't understand it but what else can I say. That's how it is.
