Photoooshop.

Nice. I’m torn between feeling bad for the poor guy who’s gonna be pounded, or feeling bad for the chicka he (might have) cheated on.
I dunno, I guess I just find it kinda pathetic that she’s not gonna beat him up on her own.

Still a little ambiguous, but definitely more on the side of he’s trying to weasel out of something he’s done, still hopeful he can get away with it. I liked the bit about the brother knownig he needed to be there for his sister more than do some pummeling, though he seems to change his mind at the end.
I think you missed a comma or two near the beginning in a compound sentence.