That image you provided is no reason to hurt him, like at all.
>He got my best friends girl to cheat on him - Relationships are tender at your age.
>He cheated on one of my other best friends - Above.
>He acts gangster - Pfft, like you loving dont.
>His pants sag really far - How is this even a reason?
>He can't spell - He was spelling pretty well on that picture.
>He said he could kick your ass - You must of provoked him for him to say that.