Posted originally on the Archive_of_Our_Own at https://archiveofourown.org/
works/7368124.
  Rating:
      Explicit
  Archive Warning:
      Underage
  Category:
      M/M
  Fandom:
      Harry_Potter_-_J._K._Rowling
  Relationship:
      Firenze/Harry_Potter
  Character:
      Harry_Potter, Firenze_(Harry_Potter)
  Additional Tags:
      Plot_What_Plot/Porn_Without_Plot, Gay_Sex, Explicit_Sexual_Content,
      Barebacking, Bestiality, Centaurs, centaur_sex, Anal_Sex, Anal_Fingering,
      Voyeurism, Large_Cock, Dom/sub_Undertones, Bottom_Harry, Top_Firenze,
      Interracial_By_Fantasy_Standards, Coming_Untouched, Come_Inflation, Rough
      Sex, Kissing, Underage_Harry, Consensual_Underage_Sex, Teacher-Student
      Relationship, Canon_Compliant, Size_Difference, Age_Difference
  Series:
      Part 1 of Fantastic_Beasts_and_where_to_fuck_them
  Stats:
      Published: 2016-07-02 Words: 1975
****** Centaur Mating ******
by kinkyasf
Summary
     Harry takes a walk through the forbidden forest, where he meets
     Firenze. The two start talking, before Firenze mounts the wizard.
Notes
     Disclaimer: I do not own Harry Potter. J.K. Rowling does.
     Sorry for any mistakes.
See the end of the work for more notes
Harry took a deep breath, enjoying the clear air of the forest. He could smell
different kinds of trees and flowers, which relaxed him immensely. Harry
started to come to the Forbidden Forest daily for a few weeks now, taking a
walk, relaxing. It helped him dealing with all the pressure from school, the DA
and Umbridge. He walked through the forest for over thirty minutes, until a
deep voice came from between the trees:

»Good evening, Harry Potter. «

Harry was startled by the sudden, unexpected noise. He spun around, heart
beating quickly, and he saw how a huge figure stepped out of the shadows. For a
moment, fear ran through his veins, until he recognized who was there.

»Hello, Firenze. «

The wise looking centaur bowed his head and gave Harry a small smile.

»It is a pleasure to meet you once again. «

»How have you been? «

»Splendid. It was very kind of your headmaster to offer me a place at your
school. «

»I'm pleased to hear that. «

Quickly they started a conversation, talking amicably. Eventually, they started
to talk about Firenze's ban from his herd.

»It's not unheard of. « the centaur explained.

»A decade before you were born a centaur stallion was banned from the herd
after mating with a human. «

»Does that happen a lot? Centaurs mating with humans? «

»It is not as rare as you might think. But only male centaurs are known to mate
with humans. Exclusively with male humans. «

»So male centaurs only have same-sex relationship with humans? Are they not
accepted in centaur society? «

»They are… tolerated. But society expects centaurs to reproduce at least once
in their life time. «

Harry nodded understandingly.

»Have you ever mated with a human? « he asked Firenze.

The centaur looked down at him with an indecipherable expression in his crystal
clear blue eyes. Harry swallowed.

»I'm sorry. That was too personal. «

Awkward silence was between them, until Firenze finally answered:

»I have never mated with a human. I have desired humans, I have wanted humans.
But most humans to not desire a centaur. «

Harry gave him a crooked smile.

»I don’t know why. Centaurs are magnificent. «

Firenze looked approvingly and proudly at Harry.

»You are an extraordinary wizard. Harry. «

The black-haired male blushed.

»Thank you. «

After they talked for another while, Harry stood up from the trunk he was
sitting on and stretched his stiff body, revealing a stripe of slightly tanned
skin between his shirt and trousers. While he stretched his wand slipped out of
his pocket, falling onto the floor. When Harry bent down to pick it up, he
unknowingly gave Firenze a nice view of his bubble butt. Harry grabbed his wand
and straightened up again, before turning around to the centaur, who quickly
moved his eyes away, feeling ashamed.

The young wizard didn’t notice the centaur's gaze on him, but he did notice
something moving between his legs. Harry took a closer look and blushed as he
saw that the moving thing was Firenze's horse dick, which hardened twitchingly.
And then he blushed even harder, when he realized why the centaur got hard.

Firenze looked mortified and took a few steps back.

»I apologize. I will leave you then. «

»No! Please, don’t! « Harry exclaimed.

Firenze froze, looking curious, but also suspicious.

»Do… Do you want me? « the wizard asked shyly.

The centaur nodded hesitantly.

»I… I don’t… I don’t m-mind that… that you w-want me. «

The tall half-human looked surprised.

»Do you want me too? « he asked eventually.

Harry didn’t know. He took a close look at the other male. Firenze had a
handsome, ageless face: Tanned skin, short brown hair and a trimmed beard, with
crystal blue eyes. His naked torso was also tanned and very muscular with
clearly defined pectoral and abdominal muscles as well as two brown-ish
nipples. His torso was completely hairless and had strong arms and huge hands.
Firenze's torso merged into an equally strong horse body, covered with brown
hair. Harry looked at the four strong legs and the long equine erection
dangling between his hind legs, leaking watery pre-cum.

»Yes. « Harry finally said.

Firenze leaned down to Harry and pressed a chaste kiss onto Harry's lips,
before withdrawing.

»Do that again, please. « Harry asked.

Firenze bent down again and when he kissed Harry, the younger boy didn’t let go
of him. Their kiss quickly became hot and wild, as untamed as the centaur’s
personality. Soon, Firenze bit Harry’s bottom lip lightly, making the boy gasp.
When his lover’s lips parted, the centaur used the opportunity to slip his
tongue into Harry’s mouth. Almost instantly Firenze dominated the kiss and the
wizard’s mouth.

Harry’s body went slack and pliant as Harry relaxed into the kiss, letting the
centaur explore his sweet mouth. Unconsciously, Harry’s hands went up and he
placed them onto the other man’s strong chest.

»Undress. « Firenze commanded.

Harry complied, eagerly taking off his loose shirt and comfortable pants.
Firenze raked his eyes over the wizard’s body, pleased with what he saw: a
relatively small and lithe body with pale, smooth and hairless skin. Harry
looked almost fragile. He had a handsome face with soft, unruly hair, striking
green eyes and tantalizingly pink and plumb lips. Harry’s ass was well-formed
and his dick was erect.

»You are beautiful. « the centaur said simply, making Harry blush.

»Prepare yourself for me. « he added a few moments afterwards.

Still blushing, Harry walked over to a tree trunk and bent over, which made
Firenze’s dick twitch in anticipation. With a muttered spell, Harry covered his
fingers with lube and brought them to his hole. Slowly, he inserted one finger
into himself, trying to relax. He pumped his finger in and out of his hole,
before adding a second one and scissoring them.

Firenze watched transfixed how the young wizard fingered himself, plunging more
and more fingers in and stretching himself wide open for the centaur. Harry
kneeling in front of him in the middle of the woods, naked and with his fingers
buried in his ass, was the most arousing sight Firenze has ever seen. Not one
of the centaur mares Firenze had sex with in the past could compare to this.

Ten minutes later, Harry wriggled his thumb into his body, alongside the other
four fingers of his right hand. Deeming himself ready, Harry quickly coated his
entrance and his inner walls with lube, before saying:

»I'm ready. «

The centaur's heart beat rapidly, as he walked to Harry. He was looming over
Harry, his strong front legs on either side of Harry's head. Firenze shifted
and his huge erection dragged wetly over Harry's lower back and left ass cheek
as Firenze tried to find the entrance to the wizard's body. The centaur had
some problems finding it, as he couldn’t see what he was doing, so Harry
reached behind him and grabbed his lover's dick. The wizard marveled at the
feeling of the hot, throbbing cock in his hand as he lined it up with his hole.

As soon as the tip of his erection was pressed against Harry's entrance,
Firenze moved forward. Harry's hand fell limply from the cock to the floor as
his body was breached. The centaur moved carefully, being aware of the size
difference between him and his human lover, so he sunk into his body slowly. It
took a couple of minutes, until Firenze stopped moving. He could only insert
two thirds of his cock into Harry, but it was good enough for Firenze: Harry
was gloriously tight. His inner walls were clamping around his equine erection,
fluttering and trying to milk him.

As for Harry… The young male couldn’t believe how big the cock inside him felt.
Being split open by the majestic dick felt magnificent for Harry. Firenze's
cock filled him properly, heating his insides. Firenze's manhood was so big
that it put constant pressure on Harry's prostate, making him turn into a
boneless, moaning and wanton mess.

Soon, the centaur started to move. At first his movements were only small,
rocking in and out of Harry gently, in order to loosen him up more. The
enormous amounts of watery clear pre-cum oozing out of his cock and into
Harry's body were helping too. One of Harry's hands wandered to his stomach,
where he could feel his lover's cock moving inside him.

»I… I'm not made out of glass. « Harry panted eventually.
Firenze grinned and sped up his thrusts, making them more powerful, which
excited Harry. The wizard knew that Firenze was still holding back, after all
he could feel the strength of the centaur's hind legs, and this knowledge
thrilled him. It was exhilarating to submit to the centaur, to let Firenze
overpower him. Every time Firenze moved his horse dick rubbed against the young
one's prostate, igniting a white, hot burning fire inside Harry, which quickly
took over every cell in his body. He couldn’t think of anything else, except
for the hard, throbbing dick inside him.

The only sounds the two males were able to hear, came from themselves: Moans
and mewls from Harry, grunts and groans from Firenze and a wet, squelching
sound every time the centaur thrust into Harry. These sounds of pleasure and
lust blocked out the rustling of the leaves, the chirping of the birds and all
the other sounds of the forest around them.

Firenze enjoyed the feeling of Harry writhing in pleasure underneath him. He
loved how his lover's inner walls clung to his dick, trying to suck it even
deeper into Harry's body. The centaur worshipped the loud moans and lustful
moans his cock punched out of Harry. He continued to fuck Harry with powerful
thrusts, until he literally fucked the orgasm out of Harry:

After a series of especially powerful thrusts, where Harry pushed his ass back
onto the thick cock, the young wizard cried out in pleasure as his orgasm hit
him suddenly and unexpectedly. Harry came untouched, moaning like a wanton
whore. His orgasm hit Harry as sudden and as strong as a tsunami wave would hit
the coast.

The centaur fucked Harry through his orgasm, drawing it out. Harry's walls
constricted almost painfully around his cock, making the wizard's body
unbearably tight. After Harry's orgasm was over, the boy was boneless and
unmoving, too satisfied to move. It took only a few more thrusts for Firenze to
cum as well:

He came while thrusting into Harry. The tip of his penis inflated (as is
typical for horses to do during an orgasm) and stretched Harry even wider.
Firenze grunted animalistically as he shot his seed into Harry. The centaur
filled Harry with his cum for over a minute, filling him to the brim, while his
cock jerked instinctively and involuntarily inside Harry.
Eventually, Firenze came down from his high and stepped back from the younger
male, pulling his softening erection carefully out of Harry, who then got up.
The wizard turned to Firenze, his belly slightly swollen from all the centaur
cum inside him, but Firenze could also see how it slowly trickled out of
Harry's puffy, gaping asshole and down his legs.

»Did I hurt you? « the centaur asked.

Harry shook his head.

»I'm sore. But that was so worth it. «

The wizard conjured a small butt plug and carefully pushed it inside him.

»What is that? « Firenze asked.

»A toy muggles use for sex. It's going to keep your cum inside me. «

Firenze came closer to Harry and caressed his face.

»It is a tantalizing image: You filled with my seed. «

Harry grinned.

»It feels very good. «

Firenze leaned down to kiss Harry slowly. When they broke apart, the centaur
asked:

»Would you want to repeat that experience? «

»Definitely. But maybe we can do it in your classroom the next time. «

The wise centaur nodded.

»We shall mate wherever you want. «
End Notes
     I got the prompt for this pairing a long while ago. I hope you liked
     it.
     Please leave kudos and comments. You can also send me prompts.
     You can also follow me on my official twitter @Gerfanfictioner
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