“There are only two criteria for being a successful B Story character (others need not apply): They must in some way represent the upside-down Act 2 world. They must in some way help guide the hero toward their life lesson or theme.”
I am happy to report that my B story character meets both these criteria. 1. He is the only character my hero meets who both believes him and has undergone a similar experience as my character. He is therefore counter to every other character in my hero’s life. 2. He does in fact help my hero learn the theme by showing my hero what letting the trauma of the past stay with you looks like and making him want to get closure on that trauma before it destroys him like it does the B story character.