Jon’s always had an especially strong relationship with his snow-white direwolf Ghost. The runt of the litter, and initially overlooked when the “true-born” Stark children picked out their puppies, Ghost quickly grew into Jon’s most loyal and intimate ally. The direwolf can rip enemies to shreds with his teeth and claws or simply terrify them into retreat and submission with equal intensity. He’s also a fully capable fur blanket in the snowy lands beyond the wall.
However, like his half-brother Bran and some other characters of Stark lineage, Jon’s relationship to his direwolf stems beyond that of a normal human-canine relationship. Jon is actually a warg, though one less developed than Bran, and can morph into Ghost’s consciousness and see the world through the wolf’s eyes. This ability is explored far more in the books, but even in the show Jon often dreams of the real-time experiences of Ghost. As an untrained and inexperienced warg (called “skinchangers” in the books), don’t expect seasons 7 or 8 to explore this in too great of detail— there are too many coming invasions to focus valuable screentime on.