Prompt: Harry is a familiar, a being that can take either human or animal form, and that shares a soul resonance with a particular witch or wizard. When they come of age, each familiar goes travelling, following that resonance to try and find their mage, and Harry is searching for his. He ends up outside an orphanage in the middle of London, certain that one of these children will be his partner and master.
We have so many Horcruxes to choose from. Or even Time-Travel if we want the original before he went bat shit insane.
He has that aristocratic air about him that it sexy.
Possessive and Obsessive to the extreme.
Capable of so much.
Harrymort:
Voldemort’s snake appearance is hot imo.
He retains that possessive and obsessive thing which I like. For his character though. irl is not okay but him being a hot mess in fiction is great!
Drama queen who loves to hear his own voice. Very human despite him trying to shed that likeness.
His obsession with Harry specifically is interesting.
There is a bond between he and Harry thanks to the Horcrux. I like using that in fics.
Thankfully HP has so much in terms of world-building so there are so many avenues available to us plot-wise for fanfiction. If you are a decent enough writer you can make anything believable. I’ve got people who didn’t understand the ships, reading my fics just because I wrote them, and coming away interested in the ships and asking for recs.
I think I like them equally because there are differences but at the same time all of the possibilities can apply.
I got a request for Heir’s Champion for the snippet.  Ask and you shall receive.  Have Harry in the Slytherin Common room.
“Come in and make yourself comfortable,” Tom said, placing a hand at the small of Harry’s back and guiding him into the room.
“Said the spider to the fly,” Harry couldn’t help muttering under his breath.
Tom threw back his head and laughed again, long and loud and rich. Harry couldn’t help but stare, drawn in by the sound that he heard so rarely. To have earned two of Tom’s genuine laughs was a rare thing, and Harry couldn’t help how pleased he felt at having accomplished it.
“You really do know me remarkably well,” Tom said with an amused grin. “Now, I need to go fetch several things. Are you comfortable waiting here?”
Harry felt apprehensive and out of his depth, but he also didn’t want to intrude on Tom’s privacy. If the man had wanted him to come up with him, he would have asked directly. So he simply nodded and gave Tom a grin that might have been a shade too tight.