Is it normal for a dog to rape a cat?

I've seen my dog do chase down a cat and rape it, like literally. He would run after a stray cat and trap it in a corner and then like bark and bite it, and when the cat would finally give up he would go and mount it >.> In the end the cat would eventually get up and walk away. The cat would then stick around in our front yard, so I think she/he liked it (my dog is very open-minded). P.S. My dog is a chihuahua mix and when he attacked it he didn't make it bleed or injure it until it was on the brink of death OK? So don't go freaking out and then lecture me. So do you think its normal for a dog to do this? Because dogs would usually just kill the cats and leave the body there, but my dog would just have like a one night stand. So I guess its a win-win situation.

Answer:

Mounting another animal is a sign of dominance in the dog-world. Your dog is simply stating his status over the cat. As long as your dog or any other animal isn't harmed, it's nothing to worry about.