Posted originally on the Archive_of_Our_Own at https://archiveofourown.org/
works/1085144.
  Rating:
      Explicit
  Archive Warning:
      Underage
  Category:
      M/M
  Fandom:
      Homestuck
  Relationship:
      Eridan_Ampora/John_Egbert
  Character:
      Eridan_Ampora, John_Egbert
  Additional Tags:
      PWP, Smut, Tentabulges, teenage_sex, Mutual_Masturbation, taken_to_a
      whole_new_level, NSFW
  Stats:
      Published: 2013-12-16 Words: 1075
****** In which John is Curious and Eridan is Horny ******
by lalaluma
Summary
     John has noticed a few things about troll anatomy and isn't afraid to
     experiment.
Notes
See the end of the work for notes
John was fascinated with the major differences in troll anatomy amongst just
the trolls themselves, to say the least. For instance, He had learned during an
incident in which Karkat had been pantsed that low blood anatomy was very close
to humans; and also that Karkat went commando. Though after some heavy petting
with Eridan he discovered that sea-dwellers had a different build
entirely. Aside from shirts, all clothes remained in place, so John couldn't
tell exactly how different they were in terms of phallus exactly, but whatever
Eridan had it was able to move versatilely, as it pressed against the fabric of
the high-blood's ridiculous pants, and rubbed itself against John's thigh.
Currently, Eridan sat in the recliner, knees apart and head back, with John
nestled into his lap, nuzzling into the troll's neck and idly watching the
mesmerizing movement. Without really thinking about it, John inquisitively
reached down to press his hand against what he assumed to be Eridan's sex. The
troll growled low in his throat, not moving his head as the organ pushed up
against his hand with a surprising amount of force, as if it actually had some
muscle to it as opposed to being made entirely of tissue. Curiosity taking over
him, John worked on getting Eridan's pants off, slightly clawed fingers joining
him in his efforts.
Pants undone and underpants that were potentially meant for women pushed aside,
the human found that Eridan was more similar to a dolphin in his anatomy than a
human. The whole thing tapered from being moderately wide at the bottom to a
tip smaller than the finger it had currently wrapped itself around, as curious
about John as he was of it. Eridan bit his lower lip, now allowing his dick to
wrap around John's wrist and tug gently in a silent command.
Kissing at the gray neck to pacify him, John tentatively grasped the base,
finding a familiar light pulse running through a vein on the underside of
Eridan's cock. The grip on his wrist tightened as he began to move his hand at
a leisurely pace, nipping at Eridan's jaw line he felt strong hands grasp his
hips, claws biting into the his flesh some. Not that this particularly bothered
the human; not nearly as much as egged him on.
Eridan whined softly, begging wordlessly for John to grip a little tighter, to
move a little faster, to do something more; but when the human failed to comply
immediately he used his hold on John's hips to roughly pull him closer and
grind aginst him, forcing the boy's own hand to push against his budding
erection. Though instead of obeying Eridan's unspoken wishes, John removed his
hand entirely. The troll hissed angrily, but stopped as a flustered John was
undoing his own pants.
The blue eyed boy slid his pants as far down his hips as he could while
straddling the other, pulling himself out with a sigh of relief. His free hand
grabbed the back of Eridan's head and yanked the troll up into a uneven and
rough meeting of lips. There was a soft shuffling sound as Eridan's earfins
twitched and moved in reaction to the kiss. More gentle now, the high-blood
massaged at John's hips, brining him well within range of the tip of his
versatile sex's reach.
John gasped and spasmed some as the flexible length of Eridan's dick wrapped
around his, pushing and gripping and flexing around him rough and quickly. Both
were moaning, but the sea dweller buried his and his teeth into the pale
shoulder in front of him, kissing and licking at the spot as if to apologize
for his asperity.
The sensation of Eridan wrapped around him like he was was entirely alien and
strange and definitely getting John off. He had never felt anything quite like
it, twisting and pulsing around his cock as he began to rock into the feeling.
This was adding friction for Eridan, who had yet to remove his face from the
shoulder he'd claimed as his own, but had moved his arms so they were looped
around the human's bare and slightly sweaty back.
Eridan already knew he wasn't going to last much longer before John decided to
start jacking him off while he was still surrounding the boy's own sex. His
moan was almost a rumbling roar, his movements becoming more frantic and
intense as he could feel the fast approach of his climax. John was altogether
thrown off by this change of pace, but the tension building in his lower
stomach was a certain indication he wasn't against it.
John had resorted to begging and pleading with Eridan for release, pumping his
hand faster over the alien dick as a bargaining tool. Between the sensations
and John's words, it was a wonder how Eridan hadn't come sooner, and when he
did he tensed up and tightened around John almost painfully. Luckily, pain was
something John Egbert was fond of to an extent. Several short swift thrusts
into Eridans still erect warmth and he'd come, gasping, peppered with moans of
the troll's name. The sea dweller winced at John's quick movements against his
oversensitive penis, but was relieved to find he wouldn't have to go down on
the boy to finish him off.
Neither pushed away from the other as John lay against Eridan's heaving chest,
watching intently as the purple gills on his sides frilled out and lay back
down against gray flesh. He reached out to touch but his hand was swatted away
from the area. "Those'll hurt if you touch 'em." Eridan mumbled, feeling a
little sleepy as John reached out again, only to be swatted once more. He could
feel his length retreating back into its flaccid position inside his body, and
shuttered some at the sensation.
John was again fascinated with the workings of a troll body, watching the
tentacle like appendage work it's way inside of Eridan's body, disappearing
behind a flap. "Hey...Eri?"Eridan gave a wordless grunt in response, pushing in
a button on the side of the chair to extend the foot rest. "How come you don't
have any balls?"
"Because I'm evvolvved." He flicked the human between his big, blue eyes.
"They're inside my body instead of out in the open. I still havve them,
though."
"It's okay, you can tell me if they just never dropped. This is a judgment free
zone."
"Leavve." 
End Notes
     Oh man has it been forever since I wrote for Homestuck. I haven't
     really been into it for a while, but JoanEgbert asked for inbox smut
     and we both ship EriJohn/SeaBreeze so I wrote her some.
     I'm sort of toying how I incorporate their quirks intp their speech.
     But only the ones that would honestly effect the way they speak. So
     like characters who use numbers in place of letters would just speak
     normally unless it gave them a lisp or something.
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