I honestly don't know. One possible reason is he looks like a border collie that attack Cindy. Another is for some reason, I get nervous around male dogs.
Ah, he's really not mean, he's just trying to make sure everything is where it needs to be, my sister said that saying he's like lord business (from the lego movie) is a pretty good way to describe him. Blue, both bob and Rex are intact males.
I've never been attacked or anything like that and the dog that jumped Cindy was female 
elevators.....
