That kangaroo didn't like the way that doughy Brit was looking at his wife.

Kangaroos, raptors of the marsupial world.

So this how kangaroos get revenge for Skippy. All right, marsupials, the gloves are off.

At first I was like, "What's with the melodramatic music?"
And then I was like, "Oh. His groin."

5 star for the groin slash description

"There is no explanation for the kangaroo's attack..."

Uh, how about this? The kangaroo was fucking sick of these humans feeding the kangaroo in front of him. Also, they're animals, not pets.

Explanation.