I play tabletop rpg with my cousins, one being older (18 years old) and the other younger (12 years old), we always play when the urge comes and we don't stop after that, me and my older cousin who I will call Teddy, we had more experience on the subject of RPG in general unlike Greg. Greg wasn't one to consume RPGs without being outside of ours, and we have no problem with that since in the sessions he manages to play quite well, in the beginning it was something simple that evolved over time, along with that the characters of each one, but that's where the problem started.
Greg started to act out of Rp, doing actions that don't match such a situation, putting things without even informing me beforehand (The master of Rpg), and narrating over me, almost taking my place. Teddy and I told Greg several times that what he was doing was completely out of Rp and that he should stop, but he just ignored it and kept doing it, one day I was presenting a new Rpg proposal that we could play (It was focused on a medieval theme pulled towards a darker and bloodthirsty side) And I was very excited, I then informed about the rules and about the rpg system and along with that I warned Greg that it was to at least manage this of putting things without my permission, but he started saying that he did this to give more immersion and surprise us (which doesn't make sense looking as a GM), I told him that I would have to know this information to see if it was consistent with the Rpg and that's why he couldn't do these things without me knowing about it, but he always disagreed no matter what I said.
like every younger cousin he said a lot of things that bothered and personally attacked me and Teddy, and after a lot of discussion about it I just got really stressed out and started cursing him and saying different things like he spoiled the sessions and didn't take nothing seriously, he didn't assume his mistakes and always wants to be right in history, he said that I was a terrible master and didn't know how to interpret characters or deepen the story, and that he did all this to make RPG better why for him I don't know how to create a story. After that I removed him from our Rpg group where we exchanged messages and I didn't put him back until now, Teddy didn't comment anything the whole time until I removed Greg, saying that he was on my side and that I really didn't like his attitude For once, Greg was texting Teddy still saying I didn't know how to make stories and I was a spoiled brat.
I am?....