Chapter 2: I Can't Stop Loving You—Or Being Jealous

The parents returned from their five-day honeymoon, looking energized and refreshed.

“Man, it’s been so long since I’ve been abroad. I was actually a little nervous!” Mikiya said with a laugh.

“It was wonderful, though, wasn't it?” Emiko added, beaming.

“I’m glad to hear it. Things are finally settling down,” Yuu replied, feeling a weight lift off his shoulders.

“They always say there’s no place like home!”

The two of them looked like they were ready to break into a hula dance at any second, laying out souvenirs on the table—mostly loud aloha shirts and boxes of chocolates. Yuu looked at the gaudy shirts and couldn't help but wonder exactly where they intended to wear them.

Mikiya, who had been in high spirits since they walked through the door, turned to Yurika. “So, Yurika, was everything okay here at the house?”

“No problems at all,” she replied smoothly. “I took perfect care of Yuu-kun. He’s such a well-behaved, dependable boy, after all.”

Yurika reported that their time alone had been perfectly domestic, carefully omitting the fact that her biological mother had dropped by, or that she and Yuu had been getting quite... intimate.

Emiko looked at her with an expression of pure admiration for her apparent sense of responsibility. “I’m truly so glad you were here, Yurika-san. Thank you for looking after Yuu.”

“O-oh, please... it was nothing special,” Yurika stuttered.

Being thanked so earnestly by Emiko made Yurika feel a sharp sting of guilt, considering she’d spent the trip entertaining some very not-sisterly thoughts.

(I-I’m safe, right?) Yurika thought frantically. (Sure, we got a little handsy in the bath and on the bed, but we didn’t cross the ultimate line, so it’s fine! It’s fine, it’s fine...)

—She is, in fact, not fine.

Once everyone had calmed down, the family gathered around the dining table. They had shared meals since moving in together, but tonight, the sense of a complete family unit felt fresh and new to both Yuu and Yurika.

Yuu had spent a long time in a single-mother household, often eating alone while his mother worked. For Yurika, her biological mother’s issues had meant home was rarely a place of peace. Though they had both harbored anxieties about their parents' remarriage, seeing how gentle and kind their new parents were brought a profound sense of relief.

But perhaps the most exciting part for both of them was that their new step-sibling happened to be exactly their type. Every glance was a thrill, every proximity a spark.

Yuu looked at Mikiya and thought, (Thank God... Onee-chan’s dad seems like a really nice guy. I was worried he’d be some scary old man, but I think I can live here comfortably with him. But still...)

A memory of the other day flashed through Yuu's mind.

(Her mother was terrifying... If she comes back, I have to be the one to protect Onee-chan! I need to grow up fast. I want to be a man who can stand up for her!)

While Yuu was busy being the protective brother, Yurika was lost in her own thoughts.

(Thank goodness... Yuu-kun’s mom seems like such a sweetheart. I was worried his parent might be toxic too, but I can relax around her. But man... Yuu-kun is just so cute every time I look at him! ♡ I could just eat him up. Wait, hold on!)

A perverted delusion bloomed in Yurika’s mind.

(I have to wait until he’s older! Otherwise, just like Yuu-kun says, the "policemen" will come and haul me away! This is the Reverse Hikaru Genji Plan!)

While Yuu was contemplating life with relative maturity, Yurika’s "I-Love-My-Brother" engine was redlining.

Suddenly, Yurika’s left hand, hidden beneath the table, began to stroke Yuu’s thigh. Her “I-want-to-dot-on-Yuu-kun” gauge had evidently hit its limit. Her elegant fingers traced patterns across his skin with a delicate, teasing touch, occasionally sliding precariously close to the crook of his leg.

Naturally, Yuu’s internal peace shattered instantly.

(Wh-wh-whaaaat?! What are you doing, you perverted sister?! We’re right in front of our parents!!)

As the erotic assault unfolded beneath the table, Yuu began to tremble, his face flushing a deep crimson as pleasure and shame warred within him.

“Oh? Yuu, what’s the matter?” Emiko asked, noticing her son’s odd behavior. “Your face is all red.”

“I-It’s nothing! Really, it’s nothing!” Yuu blurted out, his heart hammering against his ribs in fear of being caught.

Underneath the table, the perverted sister’s hand was relentless. Between the ticklishness, the pleasure, and the sheer embarrassment, Yuu couldn't stop twitching.

Of course, his reaction only served to excite Yurika even more.

“Do you have a fever, Yuu-kun?” Yurika asked innocently, reaching out with her right hand to touch his forehead. Her left hand, however, continued its mischievous exploration of his thigh. She was in full-on prankster mode.

“Doesn’t seem like a fever. Oh my... could it be that you’re just embarrassed to be sitting next to your Onee-chan?”

Yurika peered into Yuu’s face with a smug, teasing grin.

“N-No! It’s not like that at all!”

“Ahaha, sorry, sorry.”

To the parents, they looked like a perfectly charming pair of siblings. Mikiya and Emiko exchanged warm smiles.

“Well, it looks like you two have already hit it off,” Mikiya said, sounding relieved. “I’m glad.”

“That’s wonderful, Yuu,” Emiko added. “I’m so happy you have such a kind older sister now.”

Watching the "harmonious" pair, the parents felt at ease. And so, with a little hidden flirting, the first dinner of the new family passed by.

◆　◇　◆

After dinner, Yuu retreated to his room, but it was only a matter of time before Yurika—still riding high on her excitement—burst in. She was clearly having the time of her life playing the part of the doting, albeit handsy, stepsister.

“Yuu-kun~, that was so much fun earlier!”

“Geez, stop pulling pranks like that!” Yuu snapped. “Don’t do that stuff in front of our parents!”

“Ufufu, sorry~. But really, it’s your fault for being too cute, Yuu-kun.”

Yuu sighed at the sight of his sister, whose attitude had completely flipped the moment they were behind closed doors. “Unbelievable.”

“Tell you what, you can tickle me back if you want,” Yurika suggested, thrusting her chest forward.

“...!”

“Go on, you can touch me anywhere you like~.”

“S-Stop it!!” Yuu wailed, averting his eyes in a panic as her voluptuous figure loomed before him. To his teenage eyes, her bouncing curves didn’t look like a sister’s—they looked like the temptations of a succubus.

“Ngh... No! I must not listen to the whispers of the devil!”

“Who are you calling a devil?!”

Yurika—the Perverted Sister turned Demonic Sister—pounced on Yuu and pulled him into a tight embrace.

“If you’re gonna talk like that, Yuu-kun, you leave me no choice!”

He was pulled flush against her, his face buried in the soft, ample pillows of her chest. Between the overwhelming squishiness, the warmth, and her intoxicating scent, he honestly couldn't tell if he was being hugged by an angel or a demon.

“Stop! Let go!” he wheezed. “People will get the wrong idea if you do this to a guy!”

“It’s okay ♡ I only do this for you, Yuu-kun.”

The words “I only do this for you” sent Yuu’s pulse skyrocketing.

(W-What is that supposed to mean?! How am I supposed to not misunderstand that?! Honestly, this perverted sister is way too touchy. I’m gonna hit my limit!)

For Yuu, who had carried a faint crush on Yurika since the day they met, her "skinship" was far too much for his heart to handle. By the time Yurika was satisfied and finally let him go, Yuu was a nervous wreck, his stamina completely drained.

“Ugh... I can’t believe I ended up with a sister like this...”

“Oh, hush. This is totally normal for siblings,” Yurika claimed, stretching out on the floor. “Don’t siblings usually, like, wrestle and stuff?”

“No! They don't! I’ve literally never heard of that!”

Whether or not siblings actually wrestled was debatable, but Yuu knew for a fact that having a high-spec, "heavy-artillery" body like Yurika’s pressed against you was not part of the standard brother-sister experience.

Oblivious (or perhaps fully aware) of her brother's plight, Yurika gave him a mischievous look.

“Hey, my shoulders are really stiff. Yuu-kun, give me a massage.”

“Hah? Do it yourself.”

“I can’t reach! My chest is so big it puts a lot of strain on my shoulders. Please? Pretty please?”

Yurika flopped onto her stomach. Her back was defenseless, the faint outline of her bra strap visible through her shirt. From her narrow waist, her rounded hips curved upward, and her meaty thighs were on full display beneath her short skirt.

“Ngh... uh...”

Yuu didn't know where to look. The skirt was dangerously short.

“Come on, hurry up! It’s a rule that little brothers have to rub their Onee-chans' shoulders!”

“There is no such rule!”

“Hurry~!” Yurika whined, kicking her legs back and forth. Every time she did, her skirt fluttered, threatening to reveal the very top of her thighs.

“Fine! I get it! Just stop moving your legs!”

Realizing that not doing it would only lead to more trouble, Yuu gave in and began the massage.

Knead, knead, knead—

“Nnn... ahhh~♡ That feels so good...”

“Don't make weird noises!”

“Ah, it’s probably hard to reach from there. You can just sit on top of me.”

Yuu prepared to mount her back, but the sheer, rounded pressure of her rear was right in his line of sight. If he sat on her to massage her, he’d inevitably be sitting right on her butt.

That was way too erotic. For a boy in the middle of puberty, hesitation was the only logical response. In the end, Yuu settled for hovering over her waist, putting all his effort into the massage without making full contact.

“Aaaah, this is paradise... pure bliss...”

“What are you, an old man?!”

Despite the banter, Yuu’s heart wouldn't stop racing. Her body heat radiated through her clothes, and the sweet scent of her hair filled his lungs. His head was spinning; he was reaching his breaking point.

(Ugh, Onee-chan... you're too sexy... Dammit, I'm getting dizzy...)

In his dazed state, Yuu tried to shift his position, but his balance failed him.

“Ah!”

Squish! Thump!

In an accidental blur of motion, he ended up draped over her back, essentially hugging her from behind.

“.................. Yuu-kun... Something is poking my butt.”

“Ugh... ah... I-I’m so sorry!!”

Having accidentally pressed his "manhood" against his step-sister’s rear, Yuu’s composure vanished completely.

(Aaaaah! She caught me again! But I couldn't help it! It’s because she’s too sexy!!)

Seeing Yuu’s face turn bright red, Yurika tried her best to smooth things over, though she was clearly just as flustered.

“I-It’s okay. Thanks for the massage, Yuu-kun.”

Naturally, Yurika was now acutely aware of him as well.

(W-w-w-wait a second! Yuu-kun is... he’s surprisingly grown-up down there! I’m supposed to be doing the Reverse Hikaru Genji Plan, but at this rate, I’m the one who won't be able to hold back!)

Between the bittersweet tension and the mounting excitement, both of them were officially overwhelmed.

◆　◇　◆

Returning home from school, Yuu noticed a pair of unfamiliar loafers in the entryway. They looked like student shoes, so he assumed one of his sister’s friends was over.

“I’m home—”

As he headed upstairs toward his room, he heard lively chatter coming from Yurika’s room. Through the slightly ajar door, he could hear what sounded like typical high school girl "girl talk."

“Come on, what about Shoma-kun? You know, the guy on the soccer team?”

“Eh? There’s nothing going on there.”

“Whaaaat?! He’s handsome, tall, and super popular with the girls!”

“Hmm... I don’t think he’s really my type.”

“Seriously, Yurika, what even is your ideal? You get confessed to all the time and you just shoot everyone down!”

Hearing that Yurika was constantly being asked out by guys made Yuu’s stomach do a nervous flip.

(I mean, yeah... Onee-chan is a total beauty. Of course guys wouldn't leave her alone... But why do I feel so... restless?)

Creak!

Yuu tried to sneak into his own room, but he accidentally made a noise, causing the conversation inside to stop dead.

“Oh? Yuu-kun, are you home?” Yurika asked, her head popping out from behind the door.

“Y-Yeah.”

As Yuu gave his moody reply, another face appeared behind Yurika. It was a girl who looked like a fashionable, modern high schooler.

“Wait, what? Is this the rumored new little brother? Introduce us!”

The friend stepped out of the room, reaching out as if to grab Yuu’s hand.

“O-okay, okay! Honestly, you’re so pushy.”

Yurika snatched Yuu’s hand before her friend could reach him, pulling him into her room as if to shield him. It was a clear "hands off" gesture. She sat Yuu down right next to her and began the introductions.

“Okay, this cute little brother here is Yuu-kun. And that woman over there is Kashiwagi Maki.”

“I’m Maki! Hey, isn't that introduction a little half-assed?!”

Yurika’s tone when introducing Yuu was dripping with affection, but her voice dropped an octave the moment she mentioned Maki. Yuu gave a wry smile and bowed politely.

“Nice to meet you. Thank you for being such a good friend to my sister.”

“Aww! So cute! What a well-mannered little brother!” Maki squealed, her energy levels spiking.

“Hey! Yuu-kun is my brother, okay?! Don't try to take him!” Yurika barked.

“I’m not taking him, geez. I’m not like you, Yurika. Seriously, having a sister with a brother complex must be tough on you, Yuu-kun.”

“I-I don't have a brother complex!”

Yurika was clearly acting strange. She looked as panicked as if someone were trying to steal her boyfriend.

“Anyway, I’m thirsty,” Maki said, gesturing for a drink. She’d probably talked herself hoarse. “Isn't it a bit hot today? I bet the little brother wants something too. Yurika, go get us something.”

Reluctantly, Yurika stood up. She walked to the door, then poked her head back in to issue one final warning.

“Listen! Do not take him!”

“I said I wouldn't!”

Once the sister left, Yuu and Maki were left alone in the room. Faced with a girl his own age for the first time, Yuu fell silent.

“So... Yuu-kun, right?”

“Y-Yes...”

“Say, do you have a girlfriend at school?”

“Eh? No, I don't...”

“Hmm, I see.”

Slide. Maki moved closer. While Yuu wasn't particularly popular with girls his own age, for some reason, older girls always seemed to take a liking to him.

“Are you shy?”

“Ugh...”

“Ohh, I like that! Scruff, scruff, scruff!”

She began aggressively messing with his hair. Yuu’s face turned bright red as the older girl doted on him.

“Aww, you’re turning red! So cute~!”

“Ngh...”

Maki seemed to have taken a real shine to him, as she continued to lean in and touch him. Right then, Yurika returned, carrying a tray of drinks.

“I brought the—Hey! What do you think you’re touching?!”

“Aw, come on, what’s the harm?”

“No!”

Yurika’s voice was sharp with emotion. She slammed the tray onto the table and tried to pull Yuu back to her side.

“Oh, lighten up. Yuu-kun is just so cute! Maybe I’ll even give him a kiss on the cheek? Mwah!”

“Ah......”

The moment Maki’s lips touched Yuu’s cheek, Yurika’s expression transformed.

Slap!

Yurika’s palm flew, striking Maki across the face.

“Eh? Wait... why?”

Maki looked stunned, unable to comprehend what had just happened. But Yurika, the one who had done the slapping, was even more shaken. Her shoulders trembled, and her beautiful face twisted in a mask of bitter agony.

“Ugh... hhh... Waaaaah! You defiled Yuu-kun! I was supposed to be the one to give him his 『First Kiss』!!”

““Ehhh......?!””

Ignoring the bewildered stares of Yuu and Maki, Yurika burst into tears. She wailed like a toddler having a massive tantrum.

“Onee-chan! I’m fine! I wasn't stolen! It’s okay!”

“Waaaaah! Yuu-kun! I hate this!!”

Yuu spent the next several minutes gently patting Yurika’s back, trying to soothe her. Eventually, her sobs subsided, and a heavy silence filled the room.

“Sniff... hic... Yuu-kun, you won't go anywhere? You'll stay by your Onee-chan’s side forever?”

“I’m not going anywhere. Honestly, you’re such a handful... You need to apologize to Kashiwagi-san. You slapped her.”

“Oh, it’s fine,” Maki said, looking awkward. “It didn't even really hurt.”

“Hic... sorry, Maki...”

“No, I’m okay. I just... I had no idea you were that much of a brocon. I should be the one saying sorry.”

“Y-Yeah...”

Maki seemed a little put off by the sheer scale of Yurika’s brother complex, but thanks to Yuu’s intervention, they managed to make up. However, seeing his sister’s obsession reach new heights, Yuu couldn't help but feel a little anxious about the future.

Now that the situation had calmed down, Yuu went back to his room to start his homework. Maki, apparently deciding to treat Yurika’s brother complex as a joke, chatted with her for a while longer before heading home. Yuu was just relieved their friendship hadn't been ruined.

“Um...”

Once Maki was gone, Yurika peeked into Yuu’s room.

“Yuu-kun... I’m sorry about earlier...”

“Onee-chan, you can’t do stuff like that. Friendships are precious, and once they break—”

As Yuu began his lecture, Yurika scrambled to explain herself.

“I-It’s not usually like that! It’s just, you and Maki were being all lovey-dovey! I thought you were being taken away from me and my brain just went into overdrive! That’s it! From now on, you’re banned from talking to girls!”

“Hah? That’s impossible. What am I supposed to do if I ever get a girlfriend...?”

At the word "girlfriend," Yurika’s face contorted.

“No, no, no, no! Absolutely not! A g-g-g-girlfriend?! You can’t! If you get a girlfriend, you’ll be getting all handsy and kissing every day, and his ○○ will do this and that and... Absolutely not!!”

Yuu wanted to point out that the only one getting handsy every day was his "perverted sister," but he kept his mouth shut. Deep down, he wanted to flirt with her, too. After all, his ideal girl was the woman standing right in front of him.

Yurika stood there, fidgeting and twiddling her fingers.

“U-um... Yuu-kun, can I have a kiss?”

“Absolutely not!”

“Ehhh! Just a little one~!”

The "Reverse Hikaru Genji Plan" was officially a bust; she was already a perverted sister who couldn't keep her hands off him.

“R-Really, just a tiny one! Just the tip... I mean, just the cheek! Please!”

“No! It’s embarrassing!”

“Whaaaat! You let Maki do it! That’s not fair! Not fair!”

“That was an accident... You’re not the Perverted Sister anymore, you’re the Annoying Sister.”

“Don't say that! Yuu-kun~!”

As Yurika’s brother complex and erotic advances intensified, Yuu found himself more and more overwhelmed by the sister he adored. He couldn't help but worry that one day, Yurika might cross a line so far out of bounds that the "policemen" really would have to get involved.