Secret Lover. SDS Robots, #4

Serrin, the manager of the Humanistic Garden gay male brothel on the Yotair pleasure satellite (SDS Robots #2) and a former SDS hybrid robot, has a secret. His home planet of Horon has been taken over by his ex-lover Prince Bedur, a usurper to the throne. Bedur was a submissive to Serrin in a BDSM relationship. But Serrin always longed for Bedur's younger brother Prince Levan, whom Bedur has imprisoned in the castle.
For the past year, Serrin has worked with Levan and Horon's loyalists to regain the monarchy for its rightful successor. The situation turns desperate as Bedur cracks down on civil rights, throwing Horon into turmoil. Serrin needs to get Levan off of Horon and safely away from Bedur. But will he and Levan finally be together at long last if that happens?