okay so this is just my theory: I think GSJ is not the villain in this show as GZY keeps on making him to be or how he is always so suspicious of him. i think GSJ could actually be trusted the most. initially I thought GSJ intentionally left so that no one doubts him and zitu clearly is an easy target to dethrone. But as far as I remember his brother gave him a secret mission i.e. his elder brother so he must trust him alot for that and probably he is actually not the one who killed the sword weilder or his brother. just my theory.