I don't know who needs to hear it or get it through their skull but understand one thing - consent is a must. Whether you "think" someone might want or allow something to do done. Be that annoyance or killjoy and ask if they actually want such thing or is it allowed to be done. If they aren't in the state to think properly or communicate, then back off until they're fit to do so.
Some people might disagree but:
I know nowadays it's seen as "desirable" to have something be forced on you without consent, but such an idea shouldn't be projected unto young teens. The right way of consent is when both parties are in agreement, conscious and aware of the situation at hand.
Sometimes, the words - "No, "Stop", "Don't" - don't register as a sign to discontinue or stop all activities. Do me the courtesy and shout every slur and insult that comes to mind if that SOB doesn't listen.
Be your brother's keeper and ask if it's okay, back off if they say no. Have a great day, kids.
