For My Master — Suz deMello

Agent Kathie Belmont has long lusted after her boss, Ross Guerrero, but has never plucked up the courage even to flirt with him. Could he be the strong but tender master she craves?

Ross wants Kathie in his life--and on her knees. But the constraints of their jobs with an ultra-secret U.S. security agency have come between them.

Until the sadistic drug-trafficker El Silencio is tempted into a deal with Ross' undercover persona--a deal that will go down at a BDSM party. With Kathie disguised as his sex slave, Ross sets out to bring down the criminal gang, and perhaps tempt Kathie into performing her role...forever.

Note: This book is mostly M/f but contains scenes of ménage and F/F intimacy.