@mruggeri2 It depends. They are known for it, but they don't necessarily eat their mates, mantises are more likely to do it when stressed and hungry but you can avoid that by keeping the female fed while she's mating if you're breeding real-life mantises.
I wonder if Koga will eventually get accustomed to people dying when they are killed.
It would be useful if he intends to keep fighting because even if he's just competing that's not always true for the opposite party.