My son’s ODD typically displays when asked to do something he doesn’t want to do. i.e. when I take away the tablet he will fight back, he will refuse to stay in a timeout, he tries to refuse going to school. He does NOT make inappropriate sexual references or discuss drugs. If I found out my son was looking at those things online, I would take away his iPad and take away the phone. I would make him write or tell the parents of his friend an apology, and I think I’d try to get him counseling. Maybe you could get him counseling through a non-profit?