Survival in Another World with My Mistress! (Light Novel) Vol. 3

Kousuke and Sylphy's Liberation Army are making big moves! But just as they're settling into their newly captured base, betrayal strikes from within their own ranks! What's a crafty survivor from another world to do when he's trapped behind enemy lines and at the mercy of three very slimy sisters? He'll have to go under all sorts of covers if he ever wants to see his dark elf mistress again!