Stars in My Pocket Like Grains of Sand
Samuel R. Delany1984

The only survivor when his home is utterly destroyed, Rat Korga is transported to a new life on the planet Velm.
Escaping a society that suppressed and enslaved him, Korga joins a vast, rich interstellar culture and finds himself sharing a world with Marq Dyeth, the person this civilization's officials have calculated to be his perfect partner.