Remind him of his age (2 years old) and fucking run.

What a bitch.

Your brother needs to be admitted into a psych ward, it sounds like he has some very serious issues.

Sounds like good harmless fun, why stop him?

Well, I hope you're a good liar or your parents might send you to a place where you'll get to enjoy the electric shocks instead.

Put it on his dick instead.

You should've let him shock himself dead

oops read it wrong. you should let his friend shock him

I don’t understand why you’re interfering with your brother’s kink. (Assuming the friend is a consenting adult.)

Put the collar on your brothers neck this time.

He's definately an asshole for going that far, but why wouldn't you let him shock his friend. Me and my friends did that to each other with an actual taser. It was actually kind of fun. a dog collar should be nothing compared to that.

A shock collar can actually damage your neck and trachea, along with everything in your throat. Especially if someone is dumb enough to keep going with it even when it starts to seriously hurt. And depending on if the friend is as dumb as op's brother, then they probably would.