Why are people expecting the MC to take revenge or this game to become like some bad ass revenge story? The game has been set up as a hard NTR from the very start. This is like expecting a vanilla game to suddenly have a NTR ending.
It has potential to become full blown meta-narrative story on NTR Renpy games. And surely is a slasher in some pathways (Khalida and now Astrid...), so if you mix it up and get Craven's "Scream", but with cuck'n'shit.
What's your favorite scary movie?
What's your favorite NTR game?
There's always some stupid bullshit reason to kill your girlfriend. That's the beauty of it all! Simplicity! Besides, if it gets too complicated, you lose your target audience.
It's the millennium. Motives are incidental.
Billy Loomis: Why? Why?! Did you hear that, Stu? I think she wants a motive. Well, I don't really believe in motive, Sid. I mean, did Norman Bates have a motive?
Stu Macher: No.
Billy Loomis: Did they ever really decide why Hannibal Lecter liked to eat people? Don't think so! See, it's a lot scarier when there's no motive, Sid. We did your mom a favor, Sid. That woman was a slut-bag whore...who flashed her shit all over town like she was Sharon Stone or something.
Stu Macher: Yeah, we put her out of her misery, 'cause let's face it, Sidney...your mother was no Sharon Stone, hmm?
Billy Loomis: Is that motive enough for you? [Sidney doesn't answer] Well, how about this? Your slut mother was fucking my father...and she's the reason my mom moved out and abandoned me. How's that for a motive? Maternal abandonment causes serious deviant behavior. It certainly fucked you up. It made you have sex with a psychopath.
Asking why someone has been cucked or blacked in Renpy game or even if NTR is avoidable becomes cliche in that manner.
I guess the author of Copycat was fed up with all formulaic NTR-based Renpy games, just as Wes Craven was tired of slasher formula and decided it's time to do another one, but with a twist on meta. Sure, a lot of female characters will die for absolutely no reason and bodycount will rise considerably, but that's a sacrifice we're willing to make anyway.