They never called him sick growing up.
Ron had proper energy as a lad, running about the Burrow's kitchen with Fred and George. He climbed high orchard trees and jumped up and down in the attic room excitedly while his Mum painted his walls a bright Chudley Cannons orange.
He has no memory of visiting Diagon Alley, when Ron turned four, escaping the watchful eye of his parents and roaming into the depths of Knockturn Alley.
But, Ron does remember being mesmorised by a single, floating light in the blackness.
Someone — SOMETHING — attacked him then.
He hasn't the faintest of what exactly happened but Ron still examines deep, scarring teethmarks in his bedroom mirror, when alone. His pale, freckled fingers dig between his collarbone and left shoulder. He still takes the medicinal drafts they give him. No one wants to answer Ron on what they're for.
"If I wasn't sick, then I wouldn't be taking these," Ron points out, upsetting his Mum smoothing back his orange fringe.
He's eleven and gulps down what smells like troll-piss and not much tastier. It's the night before boarding the Hogwarts Express.
There's no reason to hide it once Ron is old enough for schooling and in the beginnings of his magical inheritance.
Fluxweed, peony, mugwart, henbane, bits of wild saffron — all of those ingredients magically brewed together and additional spells form the highest potency of Ron's draft. A single drop of Common Green Welsh's blood. And, of course, ginger for an upset stomach.
Obtaining the dragon-blood for the monthly draft comes at a cost. Maybe it's why they are routinely poor. Ron doesn't like to think about that. He doesn't want to be the family burden. He suspects a part of the reason Charlie started working with dragons, and grew more and more fascinated by them, had been the urgency to manage and possibly cure Ron.
Harry and Hermione might be the only ones who have ever seen Ron's scars, besides Madam Pomfrey.
They ask questions (and too many it feels like) and hug him, treating him like Ron needs sympathy. He doesn't. He just needs them to listen.
"I recognise ss'at odour," Krum announces, his voice low and gruff.
Ron's fourteen and this year is special — his Quiddich idol caught the Snitch at the World Cup. Viktor Krum has been attending classes alongside Ron and walking his hallways, and Ron stares like a lovestruck git, torn between jealousy of Hermione getting Krum's attention and Krum having his friend's attention.
Pomfrey's medicinal draft cradles against Ron's hands, its cork popped.
"I," Ron breathes out, flustered. "It's… erm, it's nothing…"
The sunlight filtering in through the Hospital Wing's widows illuminates the sharp lines in Krum's thin, handsome face. "It counteracts Incubo toxins in ss'e bloodstream," he says quietly, curiously eyeing Ron. "You vere infected?"
Ron's heart sputters and sinks. To his increasing mortification, his face reddens visibly when Krum's fingers touch his.
"Long time ago."
"I see," Krum mumbles, examining the glass vial. His thick, dark brows furrowing as he reads the label. "Vell, it is said among scholars that pure dragon's blood has properties to suppress ailments you may experience. It vill keep ss'e Incubo ss'rall from manifesting inside you. But a potion ss'is complex takes time to make. Ss's very valuable." Krum gives him a faintly impressed look, nodding to Ron's draft in his own hand and then gazing up at him. "I ss'ink you are very fortunate, Ron Vveasley."
Ron gapes back at him, stunned. "How do you know so much about this?" he asks.
Krum's lips upturn into a sliver of a warm smile.
"Unlike your Hogvarts, Durmstang Institute is not afraid to explore the mysterious and dark," he explains, passing Ron back his already drained vial. The contents of Ron's stomach sloshing and queasy from his nervousness. "Ve do ss'is to protect ourselves and to learn ss'at vhich must be learned to subdue our enemies."
Instead of going to Astronomy, Ron spends time in the back of the Hospital Wing, sitting across from Krum on another cot.
Krum apparently came in for a migraine after practicing his Transfiguration for the Second Task. Krum tells him that his uncle's brother had been exposed to the Incubo's toxin from a leg-wound. They managed to cure him over time, but he already reached the height of his magical inheritance. He expects Ron had been too young to receive the same treatment from St Mungo's Hospital.
"Back vhere I am from, ve have vays to control it viss'out suppressing ss'e full potential of your magic." Krum notices Ron's frustrated, grim expression on the subject. "You should not be ashamed of vhat you are."
"What am I?" Ron mutters, rolling his eyes slightly.
He doesn't expect Krum to stand up, approaching him and lifting a hand. Krum's fingertips brush to Ron's freckled chin, mapping him, admiring him, leaving pinpricks of gentle, fleshy heat. "Different," he admits, Krum's smile suddenly reappear and it's like the turning of the seasons in Ron's chest. From frigid and barren into a slow, resonating warmth. "Vonderful. Strong."
Wonderful — that's not a word Ron ever heard in his direction. Daft, rubbish, tosser, arse — that's all well and good. But wonderful?
Ron opens his mouth silently. He backs away, reddening darker as Madam Pomfrey returns, shooing him out.
Krum sends him a pleasant and apologetic look, joining her by another section of the Hospital Wing.
For the rest of his schooling and after the War, Ron's secret never materalised in Rita Skeeter's columns.
Krum's letters deliver regularly to Ron's location, at first from Durmstang and then addressed from Krum's home in Bulgaria. Hermione has been receiving letters as well, but as friends. Ron doesn't mind. He's thrilled to see Krum again, after years and years, shaking his hand vigorously in Krum's small, dimly lit cabin and accepting a light and cordial kiss to both of Ron's cheeks.
There's no brown and woolen uniform or rich red cape upon Krum's shoulder. He's dressed rather informally in dark, fitted trousers and a wolf fur-lined cloak. Ron catches himself staring at the curve of Krum's bum while they're getting settled. Daft.
Ron's medicinal drafts are no longer as effective to him.
He needs weekly suppressants and potions that can't be afforded and puts his immediate health at risk. Krum promises there are more alternatives in his homeland. Upon a visit to a famed and local med-wizard, Ron discovers it's true. The best way to eliminate the Incubo toxin from Ron's system, and return to a normal life pre-infection… he has to completely release the hormones, under trusted supervision, and get himself impregnated.
That leads to more questions: will it work entirely? What happens to Ron's magic? Will the child be an Incubo or worse?
"Did you know ss'at Merlin had been a child of an Incubo?" Krum's whisper drifts over him. Ron shakes his head, panting, arching his nakedness against Krum's hips. He feels sweaty and hot, but exhausted in a good way. His bright orange hair wet and sticking up. Every inch of Krum's cock tightly filling him. "He vas ss'e most poverful vizard in memory. Do not vorry."
He feels his arse thumping down against Krum's sheets, hard and rhythmic, unable to concentrate on a specific sensation when Krum bends over and presses his mouth over Ron's pale lips. It's a kiss that dizzies him, slackens Ron's lips and teeth apart so the older man licks inside. He groans when Ron braves a loud, rough suck on Krum's tongue, smiling widely against him.
He feels it. He feels that burning, ugly presence within him threatening to crest with Ron's orgasm. His thrall intensifying.
It should be Krum. Maybe it was always meant to be Krum — his idol, his friend, his lover.
Krum, thankfully, has already been shagging him, unaffected by the Incubo's manipulative hormones.
He tugs on Ron's stiffened cock, easing him into a quick, filthy orgasm before focusing back on his thrusting. Krum groans again, after a long moment, firmly pushing up Ron's arse and holding himself deep, giving him the full, thick length of his cock. Ron shudders, gripping onto Krum's hand splayed over his belly, eyelids falling shut. He imagines the hot, gushing fluid kindling a fire. Creating new life.
"You vant a son or a daughter?"
"Ah, hhah, d-doesn't matter," Ron gasps, squirming and unclenching on his back when Krum's cock slips out of him. A string of white-translucent cum gleams on the tip, connecting to Ron's sore-stretched, pinkened hole. "As long as they're alright…"
"You vill be alright too, sladurche…"
Krum's dark, smiling eyes are the first thing Ron sees when he reopens his eyes.
They silently regard each other and then kiss, brief and tender. Krum wipes himself off, getting up for the loo and offers a clean, newly dampened cloth. Ron mutters a 'thank you' when the older man steadies him, rubbing his leg. The familiar, heavy weight already feels like it's gone from Ron's chest.
He doesn't have to live with being different alone.
That's the important part.