Gerard is heartless. Peter is without guilt or a soul. They hate everyone who isn’t blood or helping them become stronger. If they weren’t on opposite sides of the spectrum, they could actually be amazingly terrible partners.
Imagine the people they could – and would – kill just to take over, to have absolute control. No-one could escape a blood-thirsty werewolf like Peter; no-one could hide from a veteran hunter as cold as Gerard. They would easily acquire an army of brainwashed people; both of them are skilled manipulators.
And yet, they wouldn’t use it against each other, aware of the futility behind it.
Peter growls when Gerard takes control of the Kanima.
The world is safe from the worst evil for another day.