I find it wierd that John pushed Maria and the MC only thinks, how sexy is Maria. John pushed your mother, in what world someone would think that in that moment? Even the most pervert guy would never think that when a loved one is being misstreated. When John is going to punch Sara he only says "I'm sorry, i'll buy you your cigarretes." Like if he was a little and powerless kid. Looks like the MC is really a pussy. If this game is not meaned to have NTR I don't see why someone would do a MC like him. I couldn't continue playing because that start was weird and didn't make sense for me. I think a normal person that see his mother being pushed will get angry and a lot more if your father is going to punch your sister, a normal guy would jump and beat him to the death. Not act like a horny guy and see all the scene and then say "Sorry for make you angry."
Still good luck. And I hope, you or anyone, don't take bad my comment, I just did an observation, I don't mean to bother or something like that.