Shoulda known

Could be Identical twins, it’s rare but sometimes both are Evil.

Neither one has a goatee though

That's exactly what the good one would say to lead the evil on to their redemption arc.

Or is that the good twin lying to preserve the possibility of good in his evil brother. Without the evil one knowing he's tested positive as such, will he still be evil?

Are these categories actually, self fulfilling proficiencies that don't serve the cultivation of humanity, and may infact, work against it?

In this way, it may be a depiction of self-sacrifice.