No you can't kill the mary sue super bull designed to perfectly cuck you and have a bigger dick than you and be better than you in everyway. His entire design is utter cancer, I honestly doubt there will be any satisfying way of ever handling him. Because he's clearly the creators dream bull. Rowan is basically designed to be sexually inferior to everyone for the creators fetish, thats why basically everyone is bigger than he is. The optional ntr stuff wouldn't be so annoying if the creator didn't go out of his way to design rowan blantantly to be such a utter loser in literally every aspect, including sexually. You know whats fun in a porn game? Having the smallest cock of all of the people that can fuck your women and your wife! Quality design for porn right there. You're not going to be able to ruin dream bulls life like he constantly does to you, or anything like that. Because the creator will protect this character, in the end its going to be some half baked scene where you "turn the tables on him" and it moves on ignoring all of the shit this guy attempts to do you constantly. Expect not to be get satisfying revenge on brother. But do expect a billion more scenes where he adds on to the torture the character can inflict on you the player character instead though. Because with the way this story is written, the only people that have consequences for their actions is the player. The player isn't allowed revenge or to put consequences on others for the horrid things they attempt to do to him. The character and player expected to just take it, and not be upset that the brother you know was trying to fuck his wife or rape his friends etc. Even though no reasonable human being would ever just say oh remember that time you attempted to rape my wife! All is forgiven! I picked the action that prevented said thing from happening and that means what you were trying to do doesn't matter!
Rowan/theplayer won't have a bunch of scenes where he steals red assholes girls, or bangs the sister in front of him repeatedly where the sister chooses Rowan over her brother and degrades the bother like he has the other girls degrade you etc. It will be some small thing thrown in with basically no meat to it, compared to everything else that gets done to the player. As for what I would want to happen? I'd want Rowan somewhere in the game drink a permanent giga dick potion to start ahegaoing the sister and getting her onto the players side, then mtfing the bother into a non futa girl and her sticking around as as sex slave for the rest of the game. With long detail scenes of you corrupting them both into your slaves. But for the reasons I mentioned above, none of this is likely or it will be meatless content because this is about Rowan being something other than a sexually inferior loser. Which is a shame, but it is what it is.