After doing a little bit of looking, I see that in the original show, Leopard's ancestors were basically the cheesy "Team Rocket" like villains of the show.
So, basically, to the Yatterman, they would have been villains that deserved to be punished. However, with so much time having passed, the recent generation of the descendants of the thieves are still paying for their ancestors' sins.
And are the most recent Yatterman as heroic as their own ancestors?
I'm actually interested to see.
