It's a pity, but it's looking more and more like keeping the horse alive will simply cause him to suffer more. 9S crouches down and reaches over to give the horse a pat on the muzzle, hoping that somehow, the horse will feel a bit better. The horse does press his muzzle into 9S' hand and snorts, but 9S doesn't know what that's supposed to mean; he doesn't speak horse.

9S rises to his feet and backs away, sword pulled from his back and hovering at his hand, wrist encircled with light. "Stand back, Rita."

He's done this before, when a moose he'd been riding had been shot down by one of the machine lifeforms. Usually the machines leave the creatures alone, but apparently the presense of an android had been enough to spur them into action. It had been better than letting the creature suffer. ...Plus, the parts could be used by androids.

Raising his hand, 9S' sword flies up. Putting his entire body into the action, 9S slams the blade into the horse's skull, metal tearing through flesh and bone and brain. The horse twitches and goes still in an instant.

The deed is done.