It made sense that they would befriend each other—their personalities were similar, and they were both creatures of magic. (55.110)
Birds of a supernatural feather flock together. In this case, Saphira and Solembum, the werecat, hang out like old pals. The pairing makes sense to Eragon, since both of them share the supernatural realm. Eragon, for his part, sort of straddles that realm. He's both human and more than human. Do you think that it's a challenge for him to exist in these two realms at the same time, belonging wholly to neither?