Xel: Broken Bond by Laura Taylor

Trained as an erotic companion, Xel has spent the past three years serving an arrogant and selfish master, constantly hoping for a life in which he’s truly appreciated, but never finding it. But all that changes when his master dies suddenly, and Xel is sent to live with Cole, his master’s estranged nephew.
After a tragedy took his family from him five years ago, Cole has retreated into a life of isolation and solitude, spending his days caring for injured and abandoned pets in the city’s largest animal sanctuary. He has little hope for the future and no interest in exploring the wider world… until unexpected news drops a confused and apprehensive slave on his doorstep.
Cole is well accustomed to caring for lost and abandoned creatures. But Xel is nothing like what he expects. Xel’s confidence and seductiveness constantly catch him off guard, and he finds himself scrambling to keep up when his ‘slave’ starts behaving in decidedly un-slave-like ways. As the tension between them grows, they are both forced to begin questioning their past decisions and trying to imagine what the world could hold, if they could only dare to hope for a brighter future.