Bunny, Bug and Pebbleshine from "Pebbleshine's kits"

"...
There was no sign of Bug. After padding to the door and poking her head outside, Pebbleshine saw the black she-cat wrestling with Bunny. The huge dog had her pinned down beneath one massive paw, while Bug’s legs waved helplessly.

Pebbleshine let out a hiss, tensing her muscles to come to her new friend’s rescue. I was right not to trust that dog! she told herself. Dogs and cats can’t be friends!

But before Pebbleshine could move, Bug wriggled out from under Bunny’s paw. Bunny bent his head, and the two of them nuzzled each other like kits before Bug hurled herself onto the dog’s back. Bunny let himself go limp, rolling over, and Bug sprang away before she was squashed.

They’re . . . play-fighting? Weird . . . , Pebbleshine thought, shaking her head. Maybe some dogs and cats could be friends, but all the same, she had no intention of getting closer to Bunny.
..."
Warrior cats, Erin Hunter