I Don't Want To Be An Omega In My Sister's Trashy Reverse Harem [BL]

"M...Mina?" Rin whispered, the name barely scraping past his throat.

The girl, the female lead, no, his sister... sat cross-legged on the infirmary bed, grinning at him like she hadn't just shattered the rules of time, space, and the fucking genre.

"What's up, Myungie!" she chirped again, waving with all the smugness of someone who'd just beaten a boss level without trying.

Rin blinked once. Then twice.

No. No, no, no.

He yanked the curtain fully shut behind him, peeking around it like a guilty thief to make sure none of the nurses were nearby. The coast was clear. Just the soft ticking of the wall clock and the gentle hum of magical equipment.

Turning back to her, Rin stepped closer, slowly, cautiously, like she was a wild beast.

Mina's grin widened, and she opened her arms like she expected a hug.

Rin's response?

He shoved two fingers in her mouth and yanked her hair.

"Mmmmph... MMMGHHH!!" she screamed into his hand, eyes wide.

"Oh, shut up, you little imp," Rin hissed, not letting go. "Do you know how many death threats I've gotten because of this garbage romance novel you wrote?!"

She kicked at him. Rin dodged.

"I read your entire cringe-fest, and now I'm the one stuck inside it with your trashy characters and their horny tendencies!"

Mina finally bit his fingers.

"OW... what the hell?!" Rin pulled back, clutching his hand.

"Not the hair, you psychopath! It's rare to have blue hair like mine," she barked, wiping her mouth and fixing her now-ruined bangs. Her makeup was smudged like a raccoon doing cosplay. "I thought you'd cry and hug me or something. I almost died, you know!"

"You dragged me into your literary dumpster fire and you want sympathy?" Rin snapped, arms flailing.

Minutes passed like that... bickering, hair-pulling, and an accidental slap. Eventually, they calmed down, Mina sitting cross-legged on the bed, Rin standing with crossed arms and twitching eyes.

"How did you get here?"

She tilted her head.

"I don't remember how I got here, though. Just woke up with a headache and your beautiful mug glaring at me."

"Well, that's comforting," Rin muttered. "So, no idea how we both ended up inside your shitty novel?"

"Nope."

"Great. That's so helpful, thanks."

He groaned, raking both hands through his hair.

"You better figure out how to get us home. Mom and Dad are probably searching for us. Did you even think about how freaked out they'd be?"

Mina blinked. Then smirked.

"Why would I want to go back? I don't have to go to school here. No exams, no math. I'm living the dream, Myungie."

She jumped off the bed and dusted off her skirt.

"Also, I'm leaving."

"What do you mean by leaving?" Rin raised a brow. "You just got here... woke up. Shouldn't you be recovering from brain trauma or whatever?"

She shrugged, stretching her arms.

"I don't wanna be the female lead."

"...Excuse me?"

"I'm not interested in playing out the story, okay?" she said it like it was the most natural decision ever.

"School? Boring. Male leads? Too clingy. Near-death drama? Pass. It's a dark romance book, I'm not mentally and physically ready to go through all of that pain,"

"But if you're not the female lead," Rin asked slowly, "then who is?"

She flashed her teeth in a wicked grin.

"You."

"...What? Are you nuts?"

She took a step forward, patting his cheek.

"You're the one the guys are flocking to like moths to flame. You've already caught Lucien's eye, and the Duke's... don't pretend you didn't see the stats. I can change the genre. Probably make it BL. It's 2025, baby."

Rin stared at her like she had just suggested he marry a cockroach.

"You're insane. Certifiably insane."

She snorted.

"And you're in denial. Just admit it... You're the new main character."

He looked like he might choke on air.

"I am not a lead! I want to go home! I want to pay bills, get yelled at by Mom, and scroll social media at 2 A.M like a normal person!"

Just then, the curtain rustled.

Rin and Mina snapped to attention.

Theron stepped in, trailed by two nurses. His eyes immediately went to Mina, who was now tucked back under the blanket like a well-behaved child. The chaos demon had transformed into a delicate flower.

'How did she do that so quickly?'

"Oh," she breathed softly, blinking like a baby deer. "I must've slipped... I don't really remember..."

Rin gawked.

This bitch!

Theron narrowed his eyes, still suspicious.

"How are you feeling?"

"I'm okay now," she murmured. "The new staff member... Rin? He helped me."

Rin gave a rigid nod, faking competence like his life depended on it. Which, to be fair, it might.

Theron's cold stare slid to him.

"I want a full report before tomorrow. Observations and treatment. I'll evaluate it."

"Y-yes, Head Doctor."

Theron left with the nurses, the sound of his boots fading down the hallway.

Mina's soft expression melted the moment they were gone.

She sat up again, arms folded.

"Okay. So, I'm gonna leave now."

"No, you're not!" Rin said, grabbing her shoulder. "I don't want to be the female lead. I'm a man!"

"You don't look like one," his sister shrugged.

"And who's the cause?"

"Me?" She raised a brow, proudly.

"I want out of this mess."

She tilted her head, gaze softening a little.

"You'll be fine. Just don't break the seal."

"...Seal?"

Mina's smile froze for half a second. Then she blinked. "Wait. You didn't finish the book, did you?"

Rin glared.

"It was 400 pages of pure suffering. I tossed it away in front of you,"

She sighed.

"Typical. Okay. So here's the thing... your character, Rin Elric, dies early in the original plot. But now that you've taken his place, there's a good chance you can avoid that if you stay low and don't break the seal."

"There's that word again," Rin muttered. "What seal?"

"You're a hybrid," she said plainly. "Your mom's a demon. Your dad's a noble. You're a hybrid omega, Myung."

Rin went silent.

"...Come again?"

"Yeah. Demon blood, omega body. Big, scary, demonic powers you haven't unlocked yet. The seal's keeping all that under wraps."

He blinked slowly.

"I'm a demon."

"Half-demon." She corrected.

"I'm a... demon."

"Yes. Yes, you are." She replied, tired of correcting him.

"..."

He sat on the edge of the bed, staring into space.

A demon. An omega. A main character. In a romance novel. A BL novel, now.

He exhaled through his nose.

"Kill me."

"No thanks." Mina beamed, reaching over to pat his head. "You're too pretty to die. What if I get killed by Lucien fucking Vortellion because I killed the new female lead?"

Rin swatted her hand.

"I'm still going to murder you."

"Get in line," she said cheerfully, already heading for the curtain.

"Wait... where are you going?!"

"I'll leave the academy and lay low. Don't worry. I'll check in sometimes. Just to see how far you've gone with the plot. Maybe, for us to return home, you, the new 'female lead' have to complete the plot,"

"Mina!"

He yelled her name but it was too late.

She slipped out of the curtain and was gone.

Rin sat there, slumped, scratching his head with both hands.

"I'm a demon omega lead in a BL harem fantasy world written by my insane sister," he mumbled.

The curtain flapped gently behind him, carried by the wind.

"I need booze..."