Bad: Walking in on your own brother having sex.
Worse: The sex is, to all outward appearances, non-consensual.
Worst:
The survivor of the assault is of the porcine persuasion.
Poll: Would you turn in your own flesh and blood if you caught them doing this?
My answer: No. Some things are still better resolved with fistfights and being locked in the attic until you die of old age.