Well, not really belligerent, at least not in my case. I'm not asking help (since I know my characters best and any advice I might follow could be untrue to the characters) so much as asking how other people go about it. If any of you have ever written a couple of characters that starts out seemingly unable to stand the other, how did you reflect that in the writing? Disagreements? Teasing? Causing each other mutual but insignificant wrongs with ensuing over-the-top and disproportionate anger? Share it!