Omega Chattel by Wendy Rathbone

At Zilly’s Chattel Farm, Alli is seen as an upstart Omega. But in reality, he is the victim of a brutal house-dad who wants to control him. Threatened with being institutionalized when he turns eighteen, Alli runs away.
Tarin is an Alpha who runs a small school from his own home for wayward Omegas. Three or four students at a time are all he can handle and his home is full. But when he meets Alli on the streets, he is compelled to bring him home.
Alli wants a better future for himself, better than selling himself on the streets, so he agrees to be a student, when what he really wants is Tarin himself. Tarin doesn’t sleep with his Omega students, and the one exception he made broke his heart.
But Alli is persistent. And not only does Tarin have a weakness for broken young men, there seems to be a spontaneous bond forming between them. The combination is turning hotter faster than they can keep up.