I don't know the story, but even if she did cheat she didn't deserve no ass whipin like that.
It ain't about deserve. You never know how someone is going to react if they've feel they have been wronged. That's why it's best for most of us to do the right thing by people and tread lightly. Only a select few can let those nuts hang at all times with no regard.
And that young man on film looks to be of the latter - the 24hr nuthangers - violent with no regard for place or time, guilty or innocent, male or female. And whoever taught him to fight taught him well - look at how he gets
everything into his punches and kicks. It's like he's either been trained or just inherently knows how to get every ounce of power from himself when he throws a punch. That broad had a good strong jaw. The others did not.
He'll get good practice on refining those techniques as he passes through whatever reformatory institutes he'll be sent to, but if he decides to continue down the rowdy route maybe some older g with a keen eye will see what I saw and give him a proper grooming cause that right there was a raw gangster in the making. Good and violent. Or even a potential young soldier in the FOI if the Nation was still on the street like that recruiting strong young Brothers. They'd have definitely taken him, disciplined him for this disgraceful act, and then straightened him right on up.
Of course the best path would be to straighten himself up and get right.