story identification - What is the name of this sci-fi novel with a male soldier and a lesbian lizard sidekick?

I read this book in the early 2000's, but I can't for the life of me remember the title or author and it's driving me crazy!

The story is in the future. Earth and most of the galaxy has been conquered by a super-intelligent computer race who no one ever sees. The main character is a male soldier who fights as a collaborator for the occupiers. He wears armor similar to "Starship Troopers", and his main job is to suppress rebellions.

He has 2 or 3 girl servants as a reward for being an officer, whose job is to give him sex on demand. One is named Hanni (I think). His best friend is a large, hulking, lizard-like alien who is female and also a soldier. In the lizard race, only the females are intelligent. The males make a sound like "bok" when having sex. His female lizard friend isn't into males though. She likes other females.

He has another soldier friend who is female. She keeps a male servant / sex slave for her own use, who has a large nose.

He suppresses lots of rebellions, including ripping the arm off some intelligent insect species. At one planet he is on, humans are mixing with some weird bird-like species. And there is another species that is intelligent and tall, with four legs.

He goes home to Earth and back to his old room. There's a holographic picture on the ceiling which his parents kept for him. It shows a woman who masturbates when he gives it a signal. (Did I mention how much sex is in this book? LOL) There is a rebellion with his old friends back on Earth. He suppresses it, before they are killed. He thinks resistance is pointless and hopeless.

At the end, his lizard friend shows him a huge weapons cache and invites him to join a secret resistance among the soldiers. He decides to join them after all, and there is hope in his life again.

I can remember so much about this book it is amazing, but I can't find it! I would really like to re-read this book, and read some other books by this same author. If someone could help me out, I would really appreciate it! Thanks :)

Answer

This is probably William Barton's When Heaven Fell.

From the Wiki entry:

Earth has been taken over by the Master Race, a galaxy-spanning empire of artificial intelligences, and the best of Earth’s survivors are recruited into the aliens' army. Athol Morrison has served for 20 years, and heads back to Earth for a brief vacation. There, he runs into old friends, and finds it easy to give into his old feelings with his childhood girlfriend, Alexandra (Alix) Moreno.

Ch. 1:

    Shells came whistling down, ruddy, garish explosions lighting up the hillside, making the ground vibrate under my boots. Shrapnel from a nearby hit came buzzing through the air, making little ticking sounds as it bounced off my armor. There were about a million of them waiting out there, the flower of their warlike nation, armed to the teeth, as dangerous as anything this world had ever produced.
    And, of course, the full muster of a standard Spahi company is 256 effectives, officers, noncoms, and troopers together. You had to feel sorry for the poor bastards. The invasion had been going on for almost a week now, and they knew what was coming.
    Maybe it was a little like this when they came to Earth. A little bit, not much. We fought harder, so much harder that six hundred thousand and more Kkhruhhuft mercenaries lay dead on Earth before it was over. Of course, they killed eight billion of us in return…
    Somewhere up there, beyond this tawny and dust-filled sky, an armed warship of the Master Race floated in orbit, bearing its cargo of software and little blue poppits, the beings who’d conquered us all. Old stories always imagine alien monsters, invaders from beyond the sky. Mighty beings, larger than men, fanged monstrosities.
    It’s what we thought the Kkhruhhuft were when they came. Only later, when we were already humiliated, did we discover they were no more than servants, slaves really, of the… intelligences who called themselves the Master Race. Not the poppits, little blue things the size of frogs, frogs with the behavior patterns of ants. Not them at all.
    Somewhere. Somewhere far back in time, the little blue frogs built anthill cities, hives that grew more complex and more complex still. Hives without mentality that evolved machines, machines that made more machines, machines that learned, slowly, ever so slowly, how to think.
    You have to wonder just when, and why, the mechanical servants of those nonsentient little blue frogs decided to call themselves the Master Race. A master race that would then go out and conquer the universe.

The servant girls ("burdars"), ch. 1:

    Later, at home, I ate dinner while I sat on the balcony of my crib and watched the sun set out of Boromilith’s lovely indigo evening sky. I’d invited Hani to have dinner with me, the way I usually signaled which pillow-geisha would be sharing my bed tonight, and we were served by the other burdars, Fyodor acting like a perfect little waiter, white linen over one arm, directing the placement of the dishes as each course was brought out, pouring the drinks himself, with a flourish.

Here's the animated holographic picture, ch.4:

    On the wall at the foot of the bed was a life-size image of a movie star I’d used as a masturbation icon when I was fourteen, misty three-D technology making her breasts and rounded hip stand out from the wall as you walked in front of her. I couldn’t remember her name, just that my parents had been angry when I traded my best hunting knife for this piece of trash. My father telling me I’d be sorry when the batteries ran out. How hard it would be, what with the Invasion and all, to get new ones...
    After a while I got undressed and turned out the light, lay down on my little bed and lay looking up at the pale, luminous flesh of my goddess. She was in her modest pose now, one knee drawn up and over, hiding the space between her legs with a smooth expanse of haunch, hands cupped under her breasts, lifting them slightly.
    I think the boy who sold me the poster didn’t even know what she could do. He’d’ve asked a higher price if he’d known. I reached out and touched the image with one extended toe, telling her to dance.
    And fire sparkled in her eyes, demure smile widening into a lascivious grin, leg sweeping away to show her vulva, one knee lifting up, inviting, hands reaching downward…
    Even now, after ten thousand burdar nights, it had the power to arouse me.

Here's the "lesbian lizard" and her family, ch. 18:

    She murmured, “Athy, that looks like something out of an old video…”
    I remembered Kong beating the shit out of that silly tyrannosaurus, which, in reality, would have made a meal out of that big, fat old gorilla. I said, “This is the friend I told you about. Her name is Shrêhht.”
    “Her breath smells like frying liver.”
    I looked up at Shrêhht, listened to the slight wheeze of her laughter. She said, “Let’s go in. I’ll introduce you to my family.”...
    “Honored Mother…” the one on the daïs. “My sister-wives Atubôrrh and Vodrêhh…” Shrêhht glanced at Sarah, perhaps getting a little tired of her uneasiness, and said, “Vodrêhh is stationed on Earth just now. She’s really taken a liking to the Gobi Plateau. We’ll have to go there next time we’re on Earth together.”...
    Shrêhht turned to the others, beckoning to a single long, rather lean Kkhruhhuft, marked with a very different sort of body paint from what I was used to seeing on soldiers... “This is my house-mate Zváiroq.”
    She whispered something in Kkhruhhuft, not wearing a vocoder, a stuttering phrase that sounded like a lion’s purr...

    And in the background, a dozen other adults, none of them painted, none of them introduced, Shrêhht leading us to a gaggle of brown-duck males, who stared at us big-eyed and murmured softly, like, “…borkborkbork…” little quirky noises all their own, a paintless nanny keeping them all together, Shrêhht running down a laundry list of meaningless names, “Rûq, Löhh, Slaaq, Mrëgh, Tuhhs, Vshât…” tapping each one in turn, eliciting a soft little “bork” in reply, running her hand gently along the back of the last one she’d named, “My favorite, I’m afraid. Quite spoiled.”