I really enjoyed the story as it is shaping up so far. For me personally, I am far more interested in the wrestling side than the incest storyline though - especially as that aspect is really full on - so I will just see how that goes for the future, but I appreciate your writing, characterization and the passion you show about wrestling world context.
Despite not originally intending this to be a visual novel on renpy you also are doing an amazing job, and I think the renders with the facial expressions are really good. Any comments are just my thoughts and I completely respect this is your project.
--- Mild Spoilers---
Some feedback.
* I think perhaps some of the threatening behavior by the main character and the sister really gave a bad impression about them.
If the story was more comical then I could just pass it off as slapstick yandere behavior, but because you had just established carefully the reality of toxic aggression and violent threats it felt really awkward. You had just shown rightly how bad the father was for behaving in in this way. Then the next thing the [sister] is threatening a random girl with smashing her with a chair for talking to the MC, and later the MC is threatening to break some guys legs for showing even a passing interest in the sister. In the context of you trying to tell a serious story with consequences about behavior this makes them look a bit unhinged and I instantly thought 'Well, they certainly inherited some things from their messed up dad.' If that is important for the story then at the very least it is perhaps something that needs to be seriously called out. As I would as a reader suggest it looks like the first seeds of them ending up like their father.
* I also think in general choices will be important and you should do you're best to factor them in. I accept that the parent and the older sister character are obligatory romances, I am not really a fan of the mum as a romance, but for the sake of the story I get it, but I think too many forced romances can be quite off-putting.