well obviously he would need to actually have her see proof. nobody's gunna believe "hey did ya know? your dads actually a horrible person" (whether directly or having her witness/"incidentally" come across some herself.) but he can start placing the seeds of doubt. send his wife some shady pictures of her husband leaving someplace with a woman (tho I'm pretty sure she's totally aware but doesnt give a shit)
damn so everyone is an unsympathetic asshole in this story except for the daughter. I wish for a genre change so they will all die from horrific sudden bloody "accidents"
Ooh right then that would be a good start too.. But also true I also believe his wife knows of his affairs but just sucks it up because of his money (I think he does earn quite good, not sure anymore lol)..?
Oof, the way I hope this with the MC is just some misunderstanding somehow... If he didn't actively participated in it, I'd be glad but at the same time, he doesn't stop it, either so he is equally guilty in bullying her, too. Really curious what the incident at the last school was where he taught, too. If that boy in that bullying tape was also related to one of his classmates.
That change in genre, I'd second that idea~

I know it isn't right to get his revenge through that bastard's daughter but in the end, I end up feeling good about him succeeding through that method.
I mean how else should he show that bastard what he did to others, he will receive it back. If he won't carry the punishment, it is bound to hit someone who is close to him. All the more because he does genuinely care for daughter (despite his cheating).