If I was a Chad, I'd won't have to worry about sex anymore. I'd kindly say no. And resume brotherhood shit. Career shit. Legacy shit.
But assuming I had to hurt her, I wouldn't do it to a 2/10 cause no point, she's already ugly, every guy will cheat on her if they can, and if they don't they'd probably have a nice productive family.
I'd hurt a 5-6/10 by using them as flashlight. Cheat on them, tell them they are crazy, find every way to pull emotional strings. Telling a bitch she is ugly only humbles them and makes them submissive. So by the previous, I can turn her into crazy bitch, and her chances of becoming a cat lady increases