Characters exist in a web of relationships. Great stories are created when the character web adds complexity and tension to your story. You can do this in a variety of ways. Characters goals can misalign from each other. This creates extreme tension especially if the goals are zero-sum meaning they couldn’t both work out. Characters goals can be the same but their means of achieving them are different. Perhaps one character believes the end justifies the means and the other character believes the means are just as important as the ends you are trying to attain. How do the characters shed light on the themes of the story? How do the characters change each other as they interact?