Just imagine a really shy cat who relies on everyone, but at the same time, headstrong and thinks he is smarter then everyone.

With the plot, Lightningcloud became sinister after Cloudpaw left, heck he named himself after his brother. So the have a very close bond. Perhaps they search for each other? Or maybe the can sense each other, dream about each other where abouts, maybe being wrong or right.. This could develop very far, but I like to see how it goes without planning to much.