Clearly Shadow the Dog is a bigger but just as harmless threat. To compare Hef is about tail sized when he is really standing and not bunched up. I admit at first Shadow the Dog was curious and did a lot of sniffing but now that she is allowed in the bunny lounge and sees Hef in his cage for a couple hours everyday she resumes this position if Hef is on the couch with us. Hef is of course the upstart troublemaker bun and gives her the old grunt when she comes over. Shadow the Dog does try to chase the wild buns but she is always leashed and can not but as far as Hef is concerned she just wants to eat his food.