"Not so for the boy in this case."
Unless he had morals, and later, when he got control of his hormones with a little age on him, he wanted to be a virgin for his wife. (There are plenty of such moral people out there.)
Or he caught a disease.
Or became a daddy at 14.
Now there, you've got a point. If she had given him a disease, or gotten pregnant, *then* the boy might have been a victim.
On your first point, I'm not sure he'd regret it even if he went thru such a life-change. Maybe it's just me, but I don't think guys regret experiences like this much.