We shouldn’t be doing this, Step-brother

Sienna

The kiss changed everything.

We went back to pretending. We had to. Slamming doors, throwing insults, fighting over who got shotgun in the car. But it was just camouflage. Underneath it, the truth hummed like static.

Every time he walked past me, I felt it.

Every brush of his hand was a spark I tried to smother.

Every look across the dinner table was too long, too sharp.

I filled pages in my journal, my handwriting jagged, desperate.

I hate him.

I hate his mouth.

I hate how much I want his mouth.

I hate that I can’t stop.

At night, the house turned into our playground. Parents asleep. Doors closed. The kitchen light flicking on like a secret signal.

One night, he leaned against the counter, watching me smoke by the open window.

“You’re still smoking,” he said.

“So what?” I exhaled a thin stream into the dark.

“Nothing.” His eyes didn’t leave mine. “You just… you look sad.”

I scoffed. “I’m not sad.”

“Yes, you are.” His voice dropped. He stepped closer, slow. “I see it.”

I hated how his words slipped under my armor. Hated how I wanted to believe him.

“I get it,” he murmured. “It’s hard. All of this.”

The ache inside me cracked open. “It’s so hard,” I whispered, before I could stop myself.

His eyes softened in a way that scared me more than his smirk ever did. “I know. I feel it too. The silence. Pretending.”

“Pretending what?”

“That we’re not dying to be alone together.”

Then his hand brushed my chin, thumb grazing my cheek. The fuse inside me lit.

The fuse was lit, but instead of exploding into something reckless, it burned slow.

His thumb lingered on my cheek, steady and warm, and for once he wasn’t smirking.

“What happened today?” he asked.

I swallowed, blinking fast. I didn’t want to talk about it. Didn’t want him to know that the whispers in the hallway, the way those girls laughed behind their hands, still cut me open. But his eyes didn’t let me hide.

“Nothing,” I lied.

He tilted his head, studying me. “You don’t cry over nothing.”

I turned away, gripping the edge of the counter until my knuckles went white. “They said I was pathetic. That I’ll never be anything. That I’ll always be just… the broken girl with two mothers.”

The words slipped out like poison I couldn’t keep in anymore. My throat burned.

For a second, silence hung between us. Then Jaxon’s hand covered mine on the counter. His grip wasn’t rough, not like usual. Gentle. Careful, like I might shatter.

“They don’t know you,” he said. “They wouldn’t last a day in your skin.”

I shook my head, a bitter laugh catching in my chest. “You don’t even like me. You’ve said worse.”

“Yeah.” His jaw clenched. “But I never meant it. Not like that.”

I looked at him, really looked. The boy who drove me crazy, who pushed every button I had, who had kissed me at that party like I meant the world to him and acted like he hates every inch of me afterwards. And right then, he wasn’t the enemy. He was the only one who saw me.

“You’re stronger than them, Sienna,” he said, his voice low. “Stronger than me, even. Don’t forget that.”

The way he said my name made my chest ache. I leaned into his touch before I could stop myself. His thumb brushed away the tear I hadn’t realized had slipped free.

“You make it sound like you care,” I whispered.

His lips quirked, but not in his usual mocking way. “Maybe I do.”

The words hit me harder than any kiss could.

For the first time in forever, I let myself lean against him. His arms came around me, steady, holding me together when I felt like I was unraveling. I should’ve pulled away. I should’ve remembered who we were, what this was. But instead, I let myself sink into the warmth of him.

Then he kissed me again, this time it wasn’t a game. It wasn’t a dare. It was a confession.

And for a few stolen minutes in that quiet kitchen, it wasn’t hate, or war, or pretending. It was just us.

We became thieves after that. Stolen moments in shadows; garage, laundry room, empty hallways. Quick, hungry touches that always stopped too soon, leaving us both burning.

But secrets weigh heavy.

It was after school, Football practice had just ended, and Jaxon still in his gear with sweat darkening his shirt leaned against his car like he owned the whole lot. The gleaming black sports car pulled stares, but so did he. Girls whispered, guys slapped him on the back. He spotted me across the lot, his smirk sliding into something only I recognized.

“Come on, Sienna,” he called, voice casual, but there was something heavier under it.

I hesitated, heart rattling, then walked toward him. He opened the passenger door like a gentleman, though his grin told me it was anything but. I climbed in, my pulse racing.

The engine roared to life, low and smooth. He pulled out of the lot, one hand on the wheel, the other sliding across the console until his fingers brushed mine. I froze. He didn’t look at me, just kept driving, but his thumb traced the inside of my wrist, a touch that wasn’t brotherly in the slightest. My breath caught.

And that’s when I saw Tyler.

He was leaving practice too, duffel slung over his shoulder, eyes narrowing as he caught the moment. His whole body stiffened, jaw locking. I knew that look. The jealous spark had turned into fire.

But it wasn’t just Tyler. Kendra was there too, standing with a group of girls by the bleachers. She followed Tyler’s gaze, then mine, and her face shifted. Suspicion, curiosity. She saw it too.

My stomach sank.

By the time Jaxon pulled into our driveway, my phone was already buzzing in my bag. I didn’t need to check to know it was Tyler.

Tyler is my ex. He  has a jealous streak that snapped sharp when he saw me smiling too sweet when Jaxon rested his arm on my laps as we exited the parking lot of the school’s sports center earlier. His texts came fast, angry:

Is he touching you? Is he looking at you? I’ll tell your dad.

Cold panic sliced through me.

Then Kendra. My best friend. She cornered me at school the next day, eyes narrowing like she was piecing together a puzzle.

“Sienna… you and Jaxon. There’s something there. I can feel it.”

I laughed it off. Lied straight to her face. But inside, the knot in my chest twisted tighter.

It was a Tuesday. The heat was suffocating, pressing against the kitchen walls. Jaxon and I were chopping vegetables for dinner, side by side but too close. My phone buzzed on the counter.

Tyler: I saw you two vividly that day. I know. Tell me the truth, or I’ll tell your dad.

The knife slipped in my hand, clattering to the tile.

Jaxon’s head turned instantly. “What happened?”

“Nothing.” My voice shook.

His brows pulled tight. “Sienna.”

“I said it’s nothing.” I bent for the knife, my fingers trembling so hard I nearly dropped it again.

He caught my wrist. His hand was steady, warm. Too much.

“Talk to me. What’s going on?”

“Leave it.” My voice cracked.

“No.” His tone sharpened. “Not this time. Is it Tyler? Did he see something?”

The words punched air from my lungs. Tears stung my eyes.

“What does it matter?” I snapped, desperate. “It’s a mistake, Jaxon. All of this. It was a mistake.”

His face shifted from hurt flashing into something darker. “A mistake?” His voice dropped, dangerous. “You’re calling this… us… a mistake?”

“Yes!” The word tore from me, raw. “It was a mistake!”

He grabbed my arm, firm. “Come with me. Now.”

“Let go!”

He didn’t. He dragged me down the hall, through the door into the garage. The air was heavy, smelling of oil and heat. He shoved me back against the wall; not hard, but enough that I felt trapped. His hands locked on my shoulders. His eyes burned into mine.

“Tell me you don’t feel this,” he demanded, his voice low and rough. “Right now. Say it.”

I opened my mouth. Nothing came. My throat refused the lie.

“Say it!” he pressed, closer now, his breath hot against my skin.

My chest rose and fell too fast. I couldn’t breathe. Couldn’t think. His forehead dropped against mine. His voice was a growl.

“You can’t. Because it’s real.”

My eyes stung. “It’s wrong.”

“Then stop me.”

His hands slid down my arms, slow, testing, like he was giving me a chance. I didn’t stop him. The silence between us crackled, alive. Anger and want tangled until I couldn’t tell them apart. His mouth hovered inches from mine. I felt his restraint, my breaking point.

And then…

“God, you make me insane.” His voice cracked rough, frustration tearing through it. His fingers dug into my shoulders, not hurting, but holding me there like I was the only thing keeping him grounded.

“Then let me go!” I fired back, though my voice shook. “If this is driving you crazy, then let me walk away. Pretend it never happened.”

His jaw clenched, his face so close I could see every flicker of anger in his eyes. “Pretend?” He let out a sharp laugh, bitter and raw. “You think I can just erase the way you look at me? The way you kiss me back?”

“That was a mistake…”

“No.” His tone cut like a blade. “Don’t you dare call it that again.”

I shoved against his chest, but he didn’t budge. “You’re my stepbrother, Jaxon! This is messed up. It’s wrong.”

He leaned closer, voice a low snarl against my ear. “Then why aren’t you fighting harder? Why do you shake every time I touch you?”

I hated him for being right. Hated myself for the way my body betrayed me.

“Because you won’t stop!” My words broke on a sob. “You keep pushing until I can’t think straight…”

“Because you don’t want me to stop.”

The air burned hot between us, his breath on my lips, my chest heaving against his. I wanted to scream at him, shove him away, lock every door between us. Instead, the truth clawed up my throat and I couldn’t hold it back.

“You’re impossible,” I whispered, hating how weak it sounded.

His eyes softened, just a fraction, but his voice stayed rough. “And you’re a liar.”

Something snapped then between us, inside me, I couldn’t tell. His hand slid to the back of my neck, pulling me closer, and this time I didn’t resist. The tension that had been choking us ignited into something else, something hotter and more dangerous.

“My back hit the cold garage wall, his body pressing hard into mine, his heat and scent overwhelming the sharp bite of grease and motor oil until that moment spun out of control and led to the night we crossed the line completely, right there in the garage.”