We shouldn’t be doing this, Step-brother

Sienna

It didn’t start with love. Or even lust.

It started with hate.

I hated him.

The day Dad brought him home, the hallway felt too small. Like even the walls were holding their breath.

Dad was grinning like he’d just closed some big business deal. His arm was wrapped around Lena, his shiny new wife. She wore a soft cream sweater, pearl earrings, hair in a neat bun that looked like it had its own security system. Perfect. Fake.

And then there was him.

Jaxon Carter. Nineteen. Taller than I expected. Lean muscle under a black T-shirt. Not smiling. Not frowning. Just looking at me in this slow, measuring way. Like he was deciding if I was a threat… or prey.

“Sienna, this is Jaxon,” Dad said, all cheerful, like he was introducing me to some distant cousin I should be thrilled about.

I gave the smallest nod possible. “Hey.”

He nodded back. Not one word. His eyes flicked down at my ripped jeans, the band tee I’d slept in, then back up to my face. His gaze had weight.

Lena’s smile was too sweet. “We’re all going to get along just fine.”

Sure. And hell was about to freeze over.

The new “family rules” appeared that night, taped to the fridge. No slamming doors. Chores split evenly. Dinner together every night at seven.

I stared at the list. “Looks like prison.”

Dad’s smile faltered. “It’s about respect, Sienna.”

Jaxon leaned against the counter, arms crossed. “Don’t worry. I’ll stay out of your way.”

His tone said the opposite.

It started small. His towel left on the bathroom floor. My trash mysteriously “forgotten” on the curb. The remote hidden under his thigh with a smug look when I searched.

Every night felt like a standoff.

Then came Tuesday.

The shower steam was still clinging to my skin when I stepped into the hallway, wrapped in a towel, hair dripping down my back. I was halfway to my room when his door opened.

He stepped out. Shirtless.

I froze.

He didn’t. He walked toward me like the hallway wasn’t narrow, like my bare shoulders and wet hair weren’t something to avoid.

“Is there a problem?” His voice was low.

I shook my head. “No.”

His gaze moved over me, slow enough to trip my pulse. “You sure?”

“Yes.” My voice cracked.

He stopped close enough that I could smell his soap. Clean, sharp, but darker underneath.

His eyes locked on mine. “Good.”

For a second, I thought he might touch me. His hand twitched like he almost would. Then he stepped back, brushed past, and disappeared into the bathroom.

I didn’t move until the door clicked shut.

After that, everything felt different.

We weren’t just avoiding each other. We were circling. Testing.

The next few days were filled with little jabs; a brush of his fingers when he passed the salt, a smirk when he caught me staring.

I told myself it was still hate. That was safer.

Then one morning,

I was halfway down the hall when Jaxon stepped out of his room, towel slung over his shoulder, toothbrush in hand. His eyes locked on the bathroom door, the same one I was already reaching for.

“Move, Blake.” His voice was flat, casual, like it wasn’t even a question.

“I was here first.” I planted my hand on the knob.

He tilted his head, smirking like it was funny. “Doesn’t look like it from here.”

“Don’t be a jerk.”

“Don’t hog the bathroom.” He leaned closer, close enough that I could smell his soap from last night’s shower. “I take five minutes. You take… forever.”

“That’s because I actually wash my hair, caveman.”

His smile sharpened. “You’d be surprised what people like about me not washing my hair.”

I rolled my eyes, gripping the doorknob tighter. “Ugh, you’re disgusting.”

He leaned his shoulder against the frame, blocking me without even trying. “Ladies first?” he said, pretending to be polite.

For a second, I almost believed him until he added, “Oh wait. That doesn’t apply to you.”

My jaw dropped. “Excuse me?”

“Bathroom’s mine. Step aside.”

“Over my dead body.”

We shoved at the same time. I was trying to twist the knob, him blocking me with his stupid arm. Our shoulders collided, our voices overlapping.

“Back off, Jaxon!”

“You back off!”

“I’m not moving!”

“Neither am I!”

The sound of footsteps on the stairs cut through our bickering.

“What’s going on here?” Dad’s voice, sharp and tired.

Lena appeared behind him, holding her coffee like it was a shield. She glanced at us. I was gripping the knob like it was life or death, Jaxon smirking like he’d already won.

Dad pinched the bridge of his nose. “Seriously? Fighting over the bathroom? You’re not five.”

“Tell her to move,” Jaxon said smoothly.

“Tell him to quit being a controlling psycho,” I snapped.

Lena sighed, sipping her coffee. “Jaxon, let Sienna go first. She has school. You can wait.”

His jaw flexed, but he stepped back. Slowly. Deliberately. Like he wanted me to know this wasn’t over.

“Fine, princess. Enjoy your mirror time.”

I shoved past him, heart hammering louder than it should for a stupid bathroom fight.

Because underneath the bickering, under Dad’s frustrated sigh and Lena’s forced smile, I knew the truth.

It wasn’t just about the bathroom.

It was about winning.

And neither of us wanted to lose.

Then came Kendra’s party.

The music was too loud. The beer was warm. I regretted saying yes before the night even started.

“Truth or dare,” Kendra announced, eyes glassy.

“Dare,” I said, because I’d rather eat glass than spill truths in front of these people.

She grinned like a wolf. “I dare you to kiss your stepbrother.”

The room went quiet.

I didn’t turn my head. I already knew where he was. Leaning against the wall, beer in hand, eyes fixed on me like he’d been waiting.

“No,” I said.

Kendra pouted. “Chicken?”

My pride flared. “Fine.”

I stood. Every step across that room felt like a choice I couldn’t undo.

When I stopped in front of him, his mouth curved. “It’s just a game, Blake.”

I leaned in, planning a quick, meaningless kiss. But the moment my lips brushed his, his hand came up, fingers curling around the back of my neck.

It wasn’t quick. It wasn’t meaningless.

His mouth moved against mine with careful hunger, like he’d thought about this for a long time. My hands curled into his shirt before I realized it.

When he finally pulled back, his forehead rested against mine. His breath was warm. “You crossed the line,” he whispered.

I didn’t trust my voice to answer.

Headlights flashed through the window. Someone shouted, “Party’s over!”

Jaxon’s hand slid away, slow. He stepped back. “We’ll talk later.”

I didn’t get the chance to ask what he meant.

Later came faster than I thought.

That night, the house was too quiet. I was brushing my teeth when his door opened.

“Come here.”

I almost laughed. “No.”

He leaned on the doorframe, arms crossed. “Scared?”

“Of you? Please.”

“Then prove it.”

My heart was a drum. Still, I walked toward him.

He stepped back into his room. I followed.

The air inside felt warmer. He closed the door with a soft click.

“You’ve been looking at me,” he said.

“You’ve been imagining things.”

His smile was slow, dangerous. “Seems like you want more than that kiss.”

“Seems like you want more than that kiss.”

Heat rushed up my neck. “You’re delusional.”

“Am I?” He moved closer, every step shrinking the air between us. “Because the way you walked in here doesn’t look like hate to me.”

I lifted my chin, trying to sound steady. “I came in because you dared me.”

“No, Blake. You came in because you wanted to.” His voice was low, threaded with something I couldn’t name. “And now you don’t know what to do with yourself.”

My pulse was a hammer. I stepped back, but his hand brushed my wrist lightly and deliberately. Not enough to trap me. Just enough to remind me he could.

“You should open the door,” I whispered.

“Say you don’t want this, and I will.” His gaze pinned me. “But if you lie, I’ll know.”

Silence stretched too long. My throat was dry. I couldn’t say the words, not without choking on them.

His smile curved, slow and knowing. He leaned down just close enough that his breath skimmed my jaw. “Thought so.”

My chest ached from how hard I was breathing. I hated that he was right. Hated that part of me wanted to lean closer instead of pulling away.

“This is wrong,” I said finally.

“Maybe.” His lips almost brushed my ear. “But wrong’s never stopped you before, has it?”

I stiffened, my pride sparking. “You don’t know me.”

“Not yet.” His voice was a promise.

I should’ve shoved him, stormed out, slammed the door. Instead, I just stood there, body betraying me with every nervous inhale.

And then…

“Sienna!”

Lena’s voice, sharp, carrying up the stairs.

We both froze.

“Dinner’s ready!”

Jaxon’s eyes stayed locked on mine, unblinking. “Go,” he said, his tone rough.

I exhaled, shaky, stepping back toward the door.

His smirk returned, faint but dangerous. “We’ll finish this later.”

I didn’t answer. Couldn’t. My legs carried me out into the hallway, but my head was still inside that room, spinning, my heart still beating like it belonged to him.