Other Possibilities.

ENVY laughed and assured WRATH, "Not my kind of fucking. I will turn your whole existence inside out."

WRATH was not cowered. It warned, "Be careful what you wish for. Within me is more fire. You will only burn yourself even if you succeed."

The two of them went back and forth, detailing just how well they would beat or fuck each other to death. 

This is not the first time they are going on this tirade, and there used to be more than the two of them who engaged in it. But the others quit after the first thousand times. They got bored of it. Only these two are willing to continue. 

It could be that they truly hate each other or that this is better than doing nothing. Either way, they will continue until someone interferes to stop them. 

LUST is usually the reasonable one, but it was GLUTTONY who stepped forward to stop them this time around.