In Equal and Opposite one night he meets his counterpart fem Harry who he has sex with but she leaves him and goes back to her dimension which makes him go mad and to get back at her, he starts raping the girls at Hogwarts to get the feeling he had when he had sex with her, keeps memory charming everyone so they don't notice, his order guard tonks follows him around suspiciously but one night he traps her and rapes her as well and starts brainwashing her. She starts changing into the fem Harry version he wants to take revenge on and he takes his frustrations on her every day to the point she is a scared mindless slave to him doing his bidding. Anyway as Ginny follows him around all the time, to get rid of her he imperios Draco and has him rape her. Back to the story he needs a ministry object that will help him use a mirror similar to mirror of erised to go to the other dimension to take his revenge on fem Harry which Tracey Davis father has so he love potions Tracey Davis and rapes her and makes her get that object for him. Memory charmed Hermione finds Tonks and Harry in a compromising situation and informs dumbledore that tonks isn't reliable to guard Harry. And Slughorn gets suspicious of him as his love potions stock is empty. So he kills Slughorn and makes it look like he drunk himself to death. Anyway it's also shown he abuses kreacher and dobby to do the evil stuff he is up to and if they fail makes them punish themselves. Dumbledore now suspicious has Tonks summoned to his office and she is so broken by Harry she changes into fem!Harry. So he legilemenses her and finds out all the shit he has been upto. Harry is torturing Tracey when Shacklebolt and other aurors show up to arrest him. He runs and by the skin of his teeth fights of the aurors and gets through the mirror and escapes to another dimension closing it in the process by taking the only object there is to open it. This is one of the darkest harry potter story I have ever read. A little scene from the fic.

--
Albus Dumbledore looked over his glasses at the small looking Auror sitting across from him.

"Tonks?" he asked kindly. The girl, he realized, fidgeted slightly before looking up at him with green eyes. Like Harry's…

"What's happened to you? Has anyone" - he avoided saying Harry - "hurt you in any way?"

She seemed to sink a bit, changing forms to an oddly familiar black haired girl unconsciously. Kingsley moved toward her from behind but Albus waved him off.

The similarity hit him at the moment, and he realized that Tonks was assuming a feminine form of Harry Potter. The only explanation he could think of was that she was unconsciously fixated on the boy

But Tonks, while not the strongest willed, was not in anyway emotionally weak. Even with her depression following Black's death and Remus Lupin's consistent evasion of her attention, she had been relatively normal, if only a bit subdued.

Harry's behavior as of late was alarming, and Albus knew he had to curb the direction the boy was headed. The world could not afford another Tom Riddle.

Albus' sharp blue eyes bored deep into Tonks' own.

 

The Downward Spiral Saga by BolshevikMuppet99 is pretty damn dark.

Spoiler: Spoilers

Harry is put in an orphanage where he's physically abused by other orphans and raped by the creepy janitor. Goes into Slytherin after meeting Draco and it only get's worse from there. Harry rapes, tortures, mutilates, and murders his way into becoming LV's right hand man, including making Horcruxes. Tonks and Ginny, specifically, do not fair well.

One of the spin offs is a Man in the High Castle type story where normal!Harry is zapped into Psycho!Harry's dimension.

 

Could you share a link to the spin-off, please?

My pick on the ultimate Dark Harry would be Frozen to the Bones by esama.

Spoiler: Spoilers

The original Harry Potter died during the Third Task. Dumbledore summoned a replacement, which turned into a cold, genocidal monster. It reads like an extreme Indy Harry played for horror.

 

Probably Indian Harry. Or alternatively Japanese Harry - not sure which counts as darker.

 

Harry Potter and the Homecoming --> Book 1 of the Downward Spiral Saga"

Echoes in the Fog -- > Man in the High Castle-style spin off

In Her Image --> Oneshot after Tonks is captured by Bellatrix in Book 5 of The Downward Spiral Saga. Holy fuck it does not go well for her.

 

I don't remember the name, but there was one by one of DLP members where Harry Rapes petunia at the beggining.

I vividly remember being genuinely disturbed by that scene and the description of the act.

That story truly showed me the limit of how dark I wanted my fanfiction.

Just reading about Harry doing such fucking heinous acts made me feel physically uncomfortable.

 

It's Fury of the hellspawn. It's pretty much straight up evil rapist Harry. At this point Petunia is already raped, Harry bites her nipples of and rapes her in every hole and murders her after and tells Vernon and Dudley what he has done (who were already tortured to near death by death eaters and hanging in the wall) as he physically beats the shit out off them, knives them and tortures them to death in front of Voldemort. Afterwards he cuts a deal with Voldemort where he takes Bellatrix as his slave for the prophecy, then takes Narcissa as his slave as he bangs her and Bellatrix in front of Draco hanging by the wall every day. Then he proceeds to brutally torture and murder snape, wormtail. And has house elves rape Draco to his death. Next he takes Tonks as his slave. Then he participates in a death eater raid and kills muggles and kidnaps a very attractive teen and her mother. He next rapes the mother in front of the teen with Bellatrix and proceds to rape her next. He decides to keep both them where their job is to service Narcissa and his slaves every day. Next he makes it back to to Grimmauld with his girls and acts out a scenerio where he was kidnapped tortured and escaped with the help of his slaves and the only he can live his with help of a rare potion. Dumbledore's naturally goes to find it. While acting sick he and tonks proceed to rape Fleur and take her as slave. Next he informs the order the weasleys are the next prime target. Here's what happens next and the last scene before it's abandoned.

--

Later that evening, the Weasley family was ransacking the Burrow, removing every odd and end that might be of use, valuable, or of sentimental value. When the dust finally settled, there was little left to mark the home as the abode of a family of nine people. Molly and Ginny Weasley were the last people in the house, looking around one last time to make sure that nothing had been missed.

Molly tiredly shouted "Ginny! Come on, love, it's time to leave. We're done here."

Ginny made to nod, but something stopped her. Instead, she found herself saying "Alright mum, I'll come after you, I just want to take one more look around the Burrow." She dismissed any odd thoughts concerning the action, reasoning that her sentimentality for the home she grew up in meant that a personal farewell was in order.

Molly nodded, but cautioned "Hurry up, Ginny, it might not be a good idea to linger too long, it's almost dark already." She stepped through the Floo and returned to Grimmauld Place.

Ginny walked down the stairs to the kitchen, and leant on the counter as she gazed at the now-empty living room. The feeling of parchment under her fingers made her turn, and she found a folded piece of parchment. Normally, she would simply have discarded it, but the parchment was of a much higher quality than what her family used. Expecting some sordid love letter between her parents, she gleefully unfolded it, and began reading.

Her horror built with every word, the first two causing her knees to buckle, making her almost fall to the ground.

Lord Voldemort,

I apologize for my abrupt departure. As you surely must recognize, an alliance of any sort between us cannot be had. I accept that my parents were casualties of war, but I cannot honestly say that revenge does not motivate me. Destiny has dictated that we shall be enemies, true, but what I told you holds true. I shall only do what destiny forces me to when I have no other motivations remaining.

As a gift, I offer you this: I misinformed the Order about an attack on the Burrow, and told them that you wished to discipline the Blood Traitors. Ginevra Weasley, the host of your memory in the Diary, shall be at the Burrow in Ottery St. Catchpole this evening. I leave it to your discretion to take action against them, if you wish.

Harry James Potter

A tear fell from her eye, splashing on her shirt. The letter caught aflame, and she released it, the flaming parchment floating to the floor in burnt pieces. She cocked her head to the side as her peripheral vision detected some movement.

Immediately she screamed, confronted by the worst horrors her dreams could produce. Lord Voldemort stood a mere three feet away from her, his expression impassive.

Before she could even attempt to scramble away, he muttered "Crucio." Screaming, she fell to the floor, completely at his mercy.

Lord Voldemort had no mercy.

Ginevra Weasley's body was discovered an hour later, by her eldest brother and her mother, both of whom fell to their knees in grief, immediately losing the contents of their stomachs. She had been drawn and quartered, glued back together in a disgusting misfit of limbs and organs, and had the Dark Mark emblazoned across every inch of her body, save her face, which was contorted in an expression of pure terror and pain. On the wall, a crude representation of the Dark Mark was drawn in her blood, the liquid trailing down at points to make it seem as if the skull was crying tears of blood.

The Weasley Family only hoped that she had died before the monster who killed her had re-attached her body so graphically

---
The whole fic is like this with extreme gore torture, rape, rough sex. I doubt I will find any other her darker Harry who can beat the one in this.

 

I remember some sci-fi fic where Harry is placed into a magic stasis, launched into outer space and is found by future humans somewhere around Jupiter. When they’re air him up he is basically a woman hating sex offender.

 

The Star Empire

 

I read a timetravel fic where Harry was sent back to 1975. Long story short he abuses blood magic rituals and becomes increasingly ruthless and violent. Culminating in him killing Dumbledore in cold blood, and creating a horcrux from his wedding ring. I've read more than my fair share of Dark!Harry fics, but something about him mutilating his soul like Voldemort didn't sit right with me.