A close up of a dog sitting on a rock in a forest

Create a detailed description of 'Rufus,' Benny's loyal canine companion in the desolate, post-human fantasy world. Rufus should be a distinctive character, visually striking yet embodying a sense of reliability and steadfastness. He should have a sturdy build with sleek, charcoal-gray fur that glistens with a faint, almost ethereal silver sheen in the pale light of this desolate world. Rufus' eyes should be a warm, deep amber, exuding a sense of wisdom and unwavering loyalty. His ears should be sharp and alert, always perked up to detect even the slightest sounds of danger in this barren landscape. His paws should be powerful, capable of swift and graceful movements, and his tail should be long and elegantly curved. Rufus should have a unique feature, a silver collar adorned with a single sapphire-blue gem at its center. This collar should not only serve as a symbol of his connection to Benny but also as a protective talisman with a subtle, magical aura that repels dark forces. Rufus' demeanor should be one of utmost devotion and companionship, always by Benny's side, ready to spring into action to protect his friend. Describe any additional distinctive characteristics or behaviors that make Rufus an exceptional and trusted companion in this bleak, post-human world