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Covetous Devotion

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“Kacchan!” Izuku screamed, bursting out of his house.

He ran as fast as he could, dashing for Kacchan’s place with the wind whipping his hair wildly around his face. His mother yelled after him, out of breath as she chased him and begged him to stop, but she was unable to keep up with her Alpha child. Izuku sprinted, chest burning. His eyes widened as he saw the waiting containment van sitting on Kacchan’s street in front of his home.

Izuku saw Kacchan’s blond hair first before he saw the rest of his best friend and shouted louder, his throat hoarse as it strained. “Kacchan!”

He didn’t make it.

“Hold up there,” Kacchan’s mother said, grabbing him by the collar and yanking back. Bigger and stronger, she held Izuku by the arms, trapping her to his chest with little to no effort. “I know he’s your friend but you need to put on the brakes, tiny Alpha. You really can’t go over there right now.”

Kacchan watched the exchange, pausing as he took a step up the open side door of the fan. His breath was heavy and his face flushed red in discomfort. Kacchan stared at Izuku with a weird glaze over his eyes as he inhaled. The aid gently pushed on Kacchan’s back urging him into the van. Izuku struggled against the older Alpha’s hold but she wouldn’t budge. Kacchan disappeared behind a closed door and Izuku whined, loud and defeated.

“Yeah, I’m going to miss him, too,” Kacchan’s mother said, eyes on the van. She didn’t let go of Izuku, her grip as tight as when she’d first grabbed him. “But look on the bright side! Knowing our luck, my son’ll be the first Omega ever to get expelled from Finishing School.”

The van pulled away and Izuku went limp in the older Alpha’s hold. She continued to wait another five minutes before it was long gone from view before she dropped him on the sidewalk, his red sneakers scuffing the concrete.

Izuku stared at the last spot he’d seen Kacchan, his chest aching. He clutched at his uniform jacket, wrinkling the black fabric. This had to be an imprint. Izuku covered his mouth, his limbs shaking from the sheer agony of his favorite person being gone. Izuku couldn’t live like this.

He needed Kacchan back.

“Can I still see him after the week ends?” Izuku asked, swallowing. “When his H-Heat is done?”

“No can do, kid,” Kacchan’s mom said. She huffed and crossed her arms. “Family are the only ones allowed to visit, but you can write him letters if you want.”

Izuku knew as much and felt foolish even asking. His mom had spelled out the same when she’d told him why Kacchan hadn’t been at school that day. He sucked in a breath and hugged himself, tears threatening to spill.

He and Kacchan were supposed to be together.

Kacchan was supposed to be an Alpha, not an Omega!

Kacchan’s mom put her hand in Izuku’s hair and ruffled it. She kept her hand, shaking his head back and forth in a light, teasing pattern. “Don’t worry, he’ll be fine. This is just a new challenge and I’m sure he’ll tackle this as head-on as everything else that he does.”

Izuku dropped his arms at his side. That was a given—Kacchan was amazing at anything and everything he put his mind to. That wasn’t the issue here. Izuku let the tears spill over his cheek. His voice wobbled. “Kacchan is going to be mated to someone else by the time I’m of age.”

“Aw, kiddo,” Kacchan’s mom said. She squeezed her fingers into his hair and stopped. She put her arm around his shoulder and tugged him into a side hug. “Trust me, in seven years you’ll meet the Omega of your dreams at a Matchmaking House and this’ll pass, just like Katsuki’ll meet someone else in a few years. You learn to move on.”

Izuku shook his head and stepped away from Kacchan’s mother. She was wrong. Izuku wasn’t going to move on. Kacchan had set the bar far too high and whatever Alpha had the pleasure to be in his company in the near future already had Izuku’s envy.

“In seven years, I’m going to get Kacchan back,” Izuku said, making the promise to himself and the world.

He turned around and walked back to his house, putting his head up and leaving Kacchan’s mother to stare at his back with a worried glance.

Izuku had work to do.

Years passed and Izuku kept to his word: He worked.

He worked every day to make sure nothing would stand in his way now that he was old enough to legally claim an Omega. Izuku had let nothing slip through the cracks. He’d studied to get into the best school that he could, he trained to make sure he was in peak physical condition, and he made sure to read up on being a proper mate to make sure Kacchan knew Izuku had grown into a desirable Alpha.

It had taken an agonizingly two years longer than he'd liked, but Izuku had succeeded in proving that he was old enough and had proof of provision to ensure that he could financially take care of an Omega.

But most important of all, Izuku had convinced Kacchan’s mother to give him the address where he’d find Kacchan. Izuku had to prove to the older woman that he was serious about his intentions through a truthful declaration and when that didn’t work, he followed up by reminding her he had every right to legally make this challenge now that he was twenty-two. Izuku had made it clear he was willing to fight her for the information if he had to and she had caved in at that point, not willing to get officials involved.

She’d told him “Good luck” with a laugh under her breath.

He hoped she appreciated he wasn’t the type of Alpha to cut off an Omega’s contact with their family, no matter how annoying they’d been over the years.

Kacchan’s mother had considered Izuku’s desires unhealthy and decided to stop “enabling him” by cutting off Deku’s contact once Kacchan had been mated and refused to give him a new address to send mail. He also suspected she had encouraged Kacchan not to answer the letters he had sent to the Finishing School and Matchmaking House when he’d found Kacchan on their online listing.

Izuku hadn’t seen or heard from Kacchan in nine years. His only contact had been stalking his Match listing and that had gone down five years ago when Kacchan had been claimed by another Alpha.

He’d needed buy a new bedroom set after he destroyed it in his anger when Kacchan's listing vanished.

“Katsuki is mated to someone else, kid,” Kacchan’s mother had said when Izuku came to ask for the name and location of Kacchan's new mate. She sighed and rubbed the side of her face as she stared Izuku down from her doorway after declaring her son was off limits. “Give it up.”

Izuku had refused.

And eventually, his stubbornness had won out.

Izuku inhaled, counting to ten to steady himself. His palms sweat and his heart raced in his chest, but he had arrived and he was going to to this. Gathering his courage, Izuku reached up to knock on the door. He waited on the step, swallowing down his nerves. He’d come too far to give up now.

He knocked again when no one answered.

“I’m coming!” he heard from the other side. The male voice was deep and smooth, slightly exasperated at his guest’s lack of patience. Izuku took a step back from the door as it opened, revealing the Alpha that had claimed Kacchan five years ago. He was tall with dark, brown hair, with warm gold eyes and a square face. “Can I help you?”

“If that’s Deku, I told you so!” Kacchan yelled from behind the door in another room.

Izuku had missed that voice and he didn’t fight the fond, relieved smile that he felt stretch his face at the sound of it.

“Ignore him,” the Alpha said, sighing under his breath. He closed the door behind him and leaned on it. “That Omega has no manners, but that’s Katsuki for you. Was there something you needed?”

Izuku squared his shoulders and straightened his back. He’d grown the past nine years, but not enough—the other Alpha still had three inches on him. “I came to challenge you for Kacchan,”

The Alpha stared before he scrunched his nose. The disbelief laced his voice as his eyes widened. “Are you Deku?”

“Yes,” Izuku said.

“Holy shit,” the Alpha said. He scratched the back of his hair and laughed. The Alpha pressed his tongue on the inside of his cheek before shaking his head in disbelief. “I thought Katsuki was yanking my leg all these years. I was sure he made up that shit about you to make himself feel better that no one else wanted him for two years.”

Izuku’s lip twitched and his fists clenched at his sides. Why would Kacchan make something like that up? Did this Alpha really not believe his mate over something that important? “Kacchan didn’t show you my letters promising I was going to come for him?”

The door opened behind the Alpha and Kacchan leaned on the door frame with his arms crossed. Izuku nearly sighed in relief, seeing Kacchan again after all these years—he looked good, healthy and eyes wicked in amusement. Kacchan tapped his Alpha in the back of his leg with his foot. “Your letters were confiscated when the Matchmaking House saw they were from a courting Alpha.”

“Hello, Kacchan,” Izuku said. He relaxed his shoulders, his voice cracking as he saw his best friend. “I’m really glad to see you and I'm really sorry I'm so late.”

“Stop,” the Alpha said, holding his hands up. He looked at Kacchan before glaring at Izuku. “I don’t know what prank you’re trying to pull, but it stops right now.”

“This isn’t a prank,” Izuku said again. He widened his stance and gripped his fists again. “I came here to challenge you for Kacchan. I’m entirely serious.”

Kacchan dropped his head against the doorway and snorted. “He’s really stubborn, even for an Alpha.”

“No one is challenging anyone,” the Alpha said, his hackles fully raised. He pointed at Izuku and said, “Go home.”

“I’m not going anywhere without Kacchan,” Izuku said.

“If you want to do this the hard way, we can do that,” the Alpha said. He straightened to his full height—a good head taller than Izuku. His Scent turned intimidating as he glared. “Walk away now while you’ve still got your dignity.”

“I didn’t train the past nine years to walk away now,” Izuku said, trusting his new muscles. He didn’t know what this Alpha’s Quirk was, but he felt confident that he could out fight him. The guy was a civilian, not a Pro Hero, so his Quirk wouldn’t be an issue. “I meant what I said and I’m going to fight you!”

“Daddy!” a shrill voice cried from inside the house. Izuku dropped his arms and straightened, seeing a tiny, blonde little girl crash into the back of Kacchan’s legs. She shook his pants leg back and forth and cried, “Ryou took my doll and won’t give it back!”

Izuku stared at the tiny child with Katsuki’s hair and the Alpha’s gold eyes and couldn’t look away. She couldn’t be more than five years old and the resemblance to her parents was unmistakable.

“Daddy’s busy,” Kacchan said, grabbing her by the collar of her dress. He turned her around and nudged her in the back with his knee. “Tell Ryou if he doesn’t give it back, daddy’s grounding him for a month.”

“He won’t listen!” The little girl whined, stomping her foot. She stayed glued in place, despite Kacchan continuing to push. “He never listens!”

“Hikari’s lying!” A small voice that had to be Ryou shouted from somewhere deep in the house. “I didn’t take her stupid doll! She’s trying to get me in trouble!”

Kacchan gave a long suffering sigh and dropped his shoulders. He held up his finger and said, “Give me like two minutes and—what’s got you mumbling?”

Deku jerked straight and snapped his mouth shut. He held the back of his neck. “Sorry, it just occurred to me that space in our apartment is going to be tight until I can look for a bigger place.”

Kacchan narrowed his eyes and pointed at the little girl who’d just noticed Izuku standing in the doorway. She squeaked and hid behind Kacchan’s leg. “Did the old hag not tell you I have kids?”

“No, she neglected to mention that,” Izuku said, imagining the older Alpha having a good laugh at his expense.

She was really, really lucky Izuku wasn’t the type to split family no matter how tempting.

“I don’t need this right now,” Kacchan said. He grabbed his kid and threw her over his shoulder. She shrieked in delight and kicked her legs back and forth. Kacchan didn’t look the slightest bit fazed by the wriggling child on his shoulder. “I’m going to sort the kids out. Please play nice and don’t start a freaking Dominance brawl on my lawn.”

He walked away leaving Izuku and Kacchan’s mate alone in the doorway.

“I take it you’re not leaving?” the other Alpha said, glancing at Izuku.

“Not a chance,” Izuku said.

He rubbed between his eyes and said, “Come on in. We can have tea or something since Katsuki’s going to be busy with the kids for a minute.”

Izuku nodded and followed him inside. “Sure.”

Kacchan had five children: two from his first litter and three from the second.

His eldest two were five years old: the little girl Hikari he’d seen at the door and her brother Ryou. The little boy glared at Izuku with Kacchan’s eyes, but shared the same brown hair as Kacchan’s mate—who Izuku had been introduced to as Kaito.

The younger three were supposed total terrors, named Shiori, Sousuke and Kousei—a little girl and twin boys. All three shared the same brown hair and gold eyes, giving no room to mistake their Alpha parent.

While the three youngest weren’t old enough yet to develop a Quirk, the oldest two had been blessed with a mix of both parent’s Quirks. Both Ryou and Hikari could summon pools of water in their hands, combining Kacchan’s ability to secrete sweat at will with Kaito’s ability to transform any liquid into pure water.

It wasn’t the best ability for fighting, but the support applications were certainly there.

“I see a single person get up from this table before their plate is empty and you’re grounded for a month,” Kacchan said, not even bother to look at Ryou sinking out of his seat. The boy snapped back into place, tugging the dish over and dropping his head on the table as he glared at the greens in the corner. Kacchan ate the last bite on his own plate and grabbed the empty dish. He set it on the counter before helping Sousuke clean a spill. “I am not in the mood today.”

Izuku made sure to clean his own plate to set a good example. Truth told, he would have done it anyway. Kacchan’s cooking was to die for and Izuku had no idea he’d take to such a skill so well. It could give his mother’s cooking a run for its money.

After they finished with dinner, Kacchan tucked his kids into bed early. Izuku could hear them complaining from downstairs while he and Kaito waited and smiled at thought of Kacchan care for his kids. Ten minutes later, Katsuki stomped back down the stairs with a scowl on his face. He joined Izuku and Kaito back at the kitchen table, crossing his arms.

The conversation started when Kacchan looked at Izuku’s biceps and his eyes widened. “When the heck did you get buff?”

“Over the past nine years,” Izuku said. He had started a new work out regimen the day after Kacchan had been taken to Finishing School and kept to it. The work had been hard, but the thought of a future with Kacchan pushed him forward. “I wasn’t sure what Quirk I’d be up against, so I had to overcompensate.”

“Okay, this is absurd,” Kaito said, rubbing between his eyes. “You're still chasing after an old crush you haven’t seen since before he hit puberty. Go to a Matchmaking House like every other Alpha with a lick of common sense and get a mate there.”

“I decided that I’d court Kacchan no matter what he presented as, even if he had been another Alpha,” Izuku said, gripping his fist. He’d made that decision practically the day he’d hit puberty himself. He hadn’t faltered in that decision once during the two years he waited for Kacchan to present. “Do you really think I’m going to change my mind now?”

“Were you this creepy when we were in middle school?” Kacchan asked, staring. He put his chin in his hand and bit his lip. “You followed me around every chance you could get, now that I think about it, so you probably were.”

Kaito covered his eyes with his hands. He breathed out and put his hands together and said, “Listen, I understand instinctual attachment, I do. But take it from someone older that it’s easily replaced. Find a mate of your own and you’ll forget about Katsuki, I promise.

“With all due respect,” Izuku said. He kept his eyes on Kacchan, older and more worn, but every inch as amazing as he’d been when they were young. “You’re wrong.”

Izuku ultimately threw the first punch.

Kaito had gone quiet after Izuku’s declaration and sighed heavily, his shoulders dropping. He let the silence hang in the air between them, thinking hard as he stared at the table.

Kacchan had said very little to either, keeping his mouth shut. It almost ticked Izuku off to see the bold man so cautious, but he supposed that came with the nature of his Class. That or Kaito had conditioned him that way—but Izuku chose not to think on that too much.

He’d have to wait and see how it went when Kacchan came home.

After another tedious ten minutes, Kaito looked up and said, “Alright, you know what? I think my first guess about all this was right. This joke has gone on long enough and we’re done with it.”

“Joke?” Izuku asked, feeling his temper rise. “I already told you that this isn’t a joke. I’m here to make a formal challenge for Kacchan—that hasn’t changed.”

“No, I don’t buy it,” Kaito said. He got up, putting his hands on the table. His Scent turned aggressive in an attempt to establish authority. “The biggest reason an Alpha challenges another for their mate is a personal vendetta against the other Alpha, which isn’t the case here since we’ve never met before. If it’s not that, an Alpha challenges another because they imprinted on the Omega accidentally through extended contact, again, not possible in this situation because you haven’t seen Katsuki in nine years.”

Kaito walked around the table and grabbed Izuku by the arm. He lifted and yanked Izuku out of the chair, dragging him away from the table. “Which means this is either a prank or you’re mad. Either way, you’re leaving right now, empty handed.”

Izuku stared at the hand around his arm. Was this guy serious? Izuku had made it very clear what he was here to do. Kaito was the older one and had the right to fight for his mate, but that’s not what was going on. Kaito didn’t believe Izuku was here for a legitimate challenge. He didn’t think of Izuku as a threat.

“Hey, Kaito,” Kacchan said, half out of his seat. His gaze went back and forth between Izuku’s face and Kaito’s grip on his arm. “Maybe you shouldn’t do that.”

“Katsuki, sit down,” Kaito Ordered. “I’ve got this.”

Kacchan dropped into the chair, a frustrated look on his face. It wasn’t pained, but it was close enough to snap Izuku’s protective instincts into play.

Izuku threw all nine years of weight training into decking Kaito to the ground.

However, not a single second of his nine years of physical training could have prepared him for a little boy tackling the back of his leg, screaming “Don’t touch my dad!”

“Ryou!” Kacchan yelled, knocking his chair over as he shot up.

Izuku threw his hands up and out, fingers spread and palms up. He didn’t move, letting the kid smack Izuku’s thigh to his heart’s content. Kacchan relaxed, dropping his head forward as it became clear Izuku had no intention of harming his child or continuing the fight while the boy was present. Izuku heard Kacchan count to ten before he walked around the table, ignoring the groaning Alpha to his left and gathered his kid.

“Ryou! You’re supposed to be asleep,” Kacchan scolded, holding the kid on his hip like he’d held the little boy’s sister earlier. “Why are you up?”

Izuku dropped his arms and took a step back to give them their space. Kaito got to his feet, rubbing his jaw and glaring at Izuku, but also sensible enough not to start a fight in front of his offspring.

“I wanted a drink,” Ryou said, voice struggling through his heavy breaths. He pointed at Izuku and yelled, “Why’d he hit dad!”

“That’s complicated and way over your tiny head right now,” Kacchan said, rubbing Ryou’s back. Red eyes glared at Izuku over his shoulder, watering as he tried to make sense of the scene he’d witness. They disappeared soon enough into Kacchan’s shoulder as the kid hiccuped. Kacchan said, “I’m taking him back to bed.”

Kacchan disappeared up the stairs with the small child that had started sobbing into his shirt.

“Get out of my house,” Kaito said.

Izuku submitted and left—but only for tonight.