I think if you act like yourself in real life. And you act like a real boy would, or a real girl. Who isn't too perfect, someone that never gets mad, or never cries, or is always happy. Then they are realistic. If you can rp as you would in the situation, and if you can treat your charrie like a version of you. Doing things you would do, when you would do them. Or maybe even the perfect version of you, things you wish you did, but never have the guts to really do. Thats more realistic.

Now if the person, was completely perfect, never messed up, or had super human powers and was able to do anything and everything in the blink of an eye. That wouldn't be very realistic. No one is perfect, no one is a super hero, and not one person can rule the world.

We want people who are normal, and themselves, and not just some perfect made up Charrie, in a made up perfect world.