The Deep Beyond - C. J. Cherryh

This omnibus volume combines two Alliance-Union novels: Hugo Award nominee Cuckoo's Egg and Locus Best Novel Award nominee Serpent's Reach.
In Cuckoo's Egg: They named him Thorn. They told him he was of their people, although he was ugly in their eyes, strange, sleek-skinned instead of furred, clawless, different. Yet he was of their power class: judge-warriors, the elite, the defenders. Thorn knew his difference was important—but not important enough to prevent murderous conspiracies against him, his protector, his caste, and perhaps against the peace of the world. But when Thorn finally learned what his true role in life was to be, that on him might hang the future of two worlds, then he had to stand alone to justify his very existence.
In Serpent's Reach: Raen a Sul Meth-maren was very young when the machinations of her distant kin erupted into a bloodbath. Years passed and Raen bided her time. Then, on a voyage to the outermost planet of the Reach, Raen encountered Betas with an intriguing tale to tell, an Azi unlike any other, and a Blue Warrior who remembered her contribution to the Hive mind. And she knew her time had come..