My Alpha Brother is my Mate

Chapter 1

Alphas Duncan Preston POV

"Come with me into the shower," she said, wrapping her small fingers tightly around my wrist and tugging gently.

She stuck out her lower lip in that classic pout she'd used since she was little, looking up at me with big, pleading eyes like a kid begging for one more cookie before bed.

I shook my head firmly and pulled my arm back just enough to break her grip. "I'm sorry, but I can't do that," I told her, keeping my voice steady even though my pulse was already starting to race.

Her brows scrunched together in confusion, and a flash of hurt crossed her face. "Why not?" she asked, sounding genuinely puzzled, almost offended.

I cleared my throat and deliberately looked away from her, staring at the tiled wall instead of her face. "Because you're not a little girl anymore," I said quietly, the words tasting heavy on my tongue.

She crossed her arms over her chest, pushing her shoulders back a little. "But I've seen you in the shower with that girl before!" she shot back, her voice cracking with a mix of jealousy and confusion.

"She was a total stranger to you, some random woman, and you didn't have any problem with her. But I'm your sister. Please?" She tilted her head and gave me those wide, puppy-dog eyes that used to work every time she wanted something when we were kids.

I felt my resolve crack almost instantly. I couldn't stand seeing her look so disappointed, so hurt. After a long second of internal battle, I let out a defeated breath. "Alright," I muttered. "Fine."

The second we stepped into the steamy shower room, she didn't hesitate.

In one quick, fluid motion, she peeled off every single piece of clothing she had on-shirt, shorts, underwear-and dropped them in a careless pile on the wet floor. I froze.

My mouth went completely dry. The body standing in front of me wasn't the skinny little kid I still pictured in my head. This was the body of a grown woman, curves in places that hadn't been there before, smooth skin glowing under the warm spray, full breasts, rounded hips, long legs. I swallowed hard, trying to force my eyes anywhere else, but they kept dragging back.

My tongue betrayed me before I could stop it. "Oh my God," I breathed out without thinking. "I thought your body was still... " You know... like a young girl's, but-" I cut myself off, taking a deep, shaky breath to try to pull myself together. My heart was hammering against my ribs.

She spun around to face me fully, water already running in little rivers down her skin. "What do you mean?" she asked innocently, tilting her head. Then, without any embarrassment at all, she pointed to her chest. "My breasts are growing now-see?" She cupped them lightly for emphasis, like she was showing me a science project.

Before I could respond, she turned sideways and arched her back a little, pushing her hips out. "And my hips are wider too... they've changed a lot lately." Her voice was casual, almost proud, like she was just sharing an interesting fact.

Then she faced me again, her expression turning a little shy for the first time. She placed one hand between her legs, covering herself modestly but still pointing with the other. "There's some hair down here now," she said softly, almost whispering. "Do you think I should shave it? Is that what grown women do?"

I felt a jolt run through my entire body-hot, electric, wrong. My hands clenched into fists at my sides. I was trembling, cold sweat breaking out on my forehead and down my back.

This was so far beyond inappropriate. She was my little sister-adopted, yes, but still my sister. I'd helped raise her. I'd protected her. And now my mind and body were betraying me in the worst possible way.

"Enough!" I snapped, louder than I meant to. She jumped a little, startled. "Stop looking at me like that. Stop... doing all of this. You're still my sister, no matter how old you are."

I wasn't even sure if I was yelling at her or at myself. Maybe both. Maybe I was trying to hammer the reminder into my own skull.

She blinked at me, surprised by the sharpness in my tone. Then, as if nothing had happened, she shrugged lightly. "Okay... but take off your clothes now."

I frowned hard, my brows pulling together. "What?!"

She gave a small, innocent shrug. "Otherwise, you'll get all soaked. Have you forgotten how showers work?" She looked genuinely confused by my reaction, like I was the one acting strange.

I could feel heat crawling up my neck. She had no idea what was happening inside me-how my body was responding in ways it absolutely shouldn't. I just wanted to get out of there as fast as humanly possible.

"No, I'm good," I said quickly, trying to sound calm. "Just turn around. I'll stay dressed."

But she wasn't having it. She clasped her hands together and bounced a little on her toes. "Please, please, please? It's just us. Like when we were kids."

I rubbed a hand over my face, exhausted by the internal war. "Fine," I muttered. "But don't look. Seriously. Don't."

I showered as fast as I could-scrubbed, rinsed, barely breathing-then bolted out of there, dripping wet and fully clothed, my mind spinning with shame and confusion.

I woke up gasping, lungs burning like I'd been underwater too long. I sat straight up in bed, rubbing my eyes hard, sweat soaking my T-shirt. "What the hell!" I hissed under my breath, cursing quietly into the dark room. "The same damn dream again. What is wrong with me?"

Mindy, my younger adopted sister, was twenty-one years old now. Not a child. Not even close. She didn't know she was adopted; she had no memory of the time before my parents brought her home. They told me she was just a baby when they got her, tiny, scared, alone. They never explained the full story, never told me where she really came from. And then they died, taking whatever secrets they had to the grave.

I flopped back against the pillows, staring at the ceiling, heart still racing. The dream felt so real every time-her voice, her body, the steam, the guilt. I hated myself for it. She was my sister. My family. The only real family I had left.

But she wasn't a little girl anymore. And no matter how many times I told myself that, the line between protector and something darker kept blurring in my sleep. I dragged a hand through my damp hair and let out a long, shaky breath.

I needed to get a grip. I needed to keep my distance. I needed to remember who we were to each other.