later in the story, the ex party of the mc meet someone who disguises herself as the mc. Everyone is suprised but the hero just flips out. He says that the mc still not sees him as his equal and that he does not think the hero can defeat the demon king on his own. The imposter says he has beneficial information about the demon king they have to fight and wants to travel with them for a while. 2 party members say it is okay, because they can really use it and they are strong enough to protect him , but the hero does not want that and here it is clear that it is because of his inferiority complex. (In the end tiana has the deciding vote and the imposter goes with them). ). In the end i think that the hero made the decision to kick him out both out of concern for the mc and his inferiority complex