Chapter 4

“Morning already…”

Sunlight filtered through the gap in the curtains, coaxing me awake. I sat up slowly, glancing at the clock. Still before my alarm—earlier than I’d expected. As I mulled over the thought, my bedroom door swung open.

“Oh, you’re already up?” Reona’s voice chirped.

“Morning, Ryouya!” Riona added with her usual energy.

As always, Reona and Riona barged into my room like it was their own. I sighed inwardly. These morning invasions had become so frequent I’d lost count, and by now, I was almost used to it. Almost. If I were still asleep, they’d have no qualms about slipping into my bed, so I’d learned to stay on guard.

“Alright, Ryouya-kun,” Reona said, clapping her hands. “Once you’re ready, shall we head out?”

“Yup, I can’t wait!” Riona beamed.

“Wait, was there some plan to go out this morning?” I asked, blinking in confusion. We hadn’t mentioned anything like that during yesterday’s end-of-term celebration, so I’d assumed today would be a lazy, free day.

“Riona suddenly got the urge to do something summer-vacation-like,” Reona explained, “so we decided on the pool.”

“That’s the deal, so get with it,” Riona added bluntly.

“That’s insanely last-minute!” I protested. Apparently, they’d decided on a whim to hit the pool. My grand plan to loaf around at home for the first day of summer vacation was crumbling before my eyes.

“By the way,” Reona continued with a sly grin, “even on days when we don’t make specific plans during the celebration, something like this always comes up. So, keep your schedule open, okay?”

“We trust you won’t let us down, Ryouya,” Riona said, her tone teasing but firm.

“Seriously…?” I muttered. Their talk yesterday about hanging out with me every day during summer vacation had sounded like a joke, but now I was starting to suspect they meant it.

“So, where are we going for the pool today?” I asked, resigned.

“Tokyo Aqualand,” Reona replied.

“I heard it’s huge, and you can spend the whole day there, so we picked it,” Riona added.

Tokyo Aqualand was a glass-domed, indoor heated pool that had opened a few years ago. With water slides, jacuzzis, a relaxation pool, saunas, restaurants, and more, it was the kind of place where you could easily lose an entire day. To think that someone like me—the poster child for introverts—would end up spending summer vacation like some extroverted normie was beyond anything I could’ve imagined just a short while ago.

“For now, I’m gonna change out of my pajamas,” I said, rubbing the back of my neck. “Could you two step outside?”

“Oh, Riona and I don’t mind,” Reona said with a mischievous glint in her eyes. “You can just change right here.”

“I mind, though…” I muttered, feeling my face heat up.

“It’s not like anything’s gonna happen if my sister and I see you,” Riona said matter-of-factly.

“Well, maybe, but still.” Her line sounded like something a guy would say to a girl. I tried to shoo them out, but it was no use. In the end, I changed while Reona and Riona watched, their gazes making the whole ordeal predictably mortifying.

Afterward, the three of us gathered at the dining table for breakfast. Ever since Reona and Riona had started practically living at my place, Mio had been quietly preparing portions for them too.

“You two have gotten so comfortable here, it’s like you’re part of the family,” I remarked, scooping up some rice.

“In that case,” Reona said with a grin, “Riona and I feel like the big sisters, and you and Mio-chan are the little brother and sister.”

“Yeah, I can’t really picture Ryouya as an older brother,” Riona teased.

“If Reona and Riona were my older sisters, it’d definitely be a handful,” I shot back, imagining the chaos. “I bet I’d be drowning in requests to pass love letters to you two.” We laughed, picturing the absurdity of it, and finished breakfast in high spirits before heading out.

At the station, I started toward the entrance, but Reona and Riona breezed right past it.

“Huh? Aren’t we going to the station?” I called after them.

“We’re stopping by the shopping mall over there to buy swimsuits first,” Reona explained.

“Our swimsuits from two years ago are too tight now,” Riona added.

That explained it. With that, we veered toward the shopping mall just across from the station.

“Alright,” I said, slowing my pace. “I’ll kill time around here, so take your time picking out swimsuits.”

“No way,” Reona said, grabbing my arm. “We want your opinion on our swimsuits, Ryouya-kun.”

“So it’d be a problem if you’re not there,” Riona added firmly.

“No, no, that’s not okay!” I retorted, already dreading the idea. Then Reona’s expression turned downright devious.

“If you don’t help us pick swimsuits,” she said sweetly, “I might accidentally let it slip to everyone that you’ve got an onahole and lube hidden away.”

“…Suddenly, I’m feeling super motivated to help you two pick swimsuits,” I said, my voice flat.

“Looking forward to it, Ryouya,” Riona said with a smirk.

Blackmailed and cornered, I had no choice but to nod reluctantly. They dragged me to the women’s swimwear section, where, as expected, I was the only guy, sticking out like a sore thumb. The stares from female customers and staff were bad enough, but helping pick swimsuits in that environment felt like a mild form of torture.

“What color swimsuits do you think would suit Riona and me, Ryouya-kun?” Reona asked, holding up a few options.

“Hmm…” I thought for a moment. “Maybe red for Reona and blue for Riona.”

“What’s your reasoning?” Riona asked, tilting her head.

“I figured red would match Reona’s bright and energetic vibe, and blue would suit Riona’s cool and calm personality,” I said, going with my gut.

Reona and Riona exchanged surprised glances.

“I thought you’d just say something like ‘anything would suit you,’” Reona said, “so this is honestly unexpected.”

“Yeah, you actually thought it through,” Riona added, nodding.

“I know by now that you two wouldn’t be satisfied unless I gave a proper answer,” I said with a wry smile.

“Wow, you’re starting to get how we sisters work, huh?” Reona said, clearly pleased.

“If you’d answered half-heartedly, we would’ve had to punish you,” Riona added.

“…What kind of punishment, exactly?” I asked, wary.

“Telling you would ruin the fun,” Reona said with a teasing lilt.

“So just look forward to it until the next opportunity,” Riona said, her smile ominous.

“I’ll pray that opportunity never comes,” I muttered. I couldn’t even imagine what their “punishment” would entail, but it was bound to be a hassle. For now, we settled on the swimsuit colors quickly, and I thought we’d be done soon. I was dead wrong. Reona and Riona were ridiculously picky about the type and design of the swimsuits, and I ended up stuck there for what felt like an eternity. By the time we finished and arrived at Tokyo Aqualand, it was nearly noon.

“Should we grab lunch before we start?” Reona suggested.

“Yeah, that way we can play longer,” Riona agreed.

“Something light would be best before swimming,” I said.

“True, I don’t want to feel sick in the pool,” Reona nodded.

With that, we headed to a restaurant inside the complex. Since it was summer vacation, Tokyo Aqualand was packed with people. We wrote our names on the waiting list at the restaurant entrance, but it took forever to get called, so the pool was probably just as crowded. When we were finally seated, all three of us ordered zaru soba, keeping it light before hitting the water.

“By the way, Ryouya-kun, what’re you doing about that open campus report assignment?” Reona asked, twirling her chopsticks.

“Ugh, don’t remind me of annoying stuff before we have fun,” I groaned.

“Sorry, sorry,” she said with a playful grin.

This summer, we’d been saddled with a tedious assignment to attend an open campus and write a report about it. Apparently, it started a few years ago because too few students from Amaki High were bothering with open campuses. The school probably thought making it mandatory would push us to participate, but the report itself was such a drag. I couldn’t help but want to gripe at the seniors whose laziness led to this.

“I’m thinking of going to Okayama City University for the open campus,” I said.

“Okayama’s pretty far from Tokyo,” Riona noted, raising an eyebrow.

“Why Okayama City University, anyway?” Reona asked, curious.

“Oh, I don’t think I mentioned, but my grandma lives in Okayama,” I explained. “So it’s the next most familiar place to me after Tokyo.” Reona and Riona still looked puzzled, so I added, “Well, my grandma’s house is actually in Kurashiki, just west of Okayama City.”

By the way, Okayama City University was a comprehensive public university with multiple faculties, known as one of the most popular in the Chugoku-Shikoku region.

“Oh, that’s the reason,” Reona said, nodding.

“Makes sense,” Riona agreed.

“Yeah, I’m planning to stop by my grandma’s house while I’m there, since it’s been a while,” I said. The trip from Tokyo to Okayama was long, so I didn’t visit often. The last time was during last year’s Obon, about a year ago.

“So, sorry, but I won’t be able to hang out with you two around the open campus dates,” I added.

“Oh, no worries,” Reona said brightly. “Riona and I are coming with you.”

“Wherever you go, Ryouya, whether it’s through fire or water, my sister and I will follow,” Riona declared.

“Wait, wait, I’m planning to stay overnight…” I said, my voice rising at their casual assumption. A day trip was one thing, but an overnight stay was a bit much.

“An overnight trip sounds even more fun!” Reona said, undeterred.

“But a guy and girls staying over together is kinda…” I mumbled, feeling awkward.

“One night or two, it’s not that different,” Riona said flatly.

Yup, they weren’t budging an inch. Continuing this argument would just lead to a stalemate, so I let it drop for now.

After lunch, we finally headed to the main event: the pool. We bought tickets at the machine, checked in at the reception, and split up at the changing rooms.

“I’ll wait at the pool entrance once I’m changed,” I called out.

“Yup, see you later, Ryouya-kun!” Reona replied cheerfully.

“We’ll head over as soon as we’re changed too,” Riona added.

I stepped into the changing room and started swapping my clothes for the swimsuit I’d pulled from my backpack. The place was packed, and finding an empty locker was a hassle.

“…Everyone here’s got such great bodies,” I muttered, glancing at the muscular high school and college-aged guys around me. At 167 cm and 55 kg, I was pretty skinny. “Maybe I should start training seriously and bulk up a bit.” My height was below average for Japanese guys, so I figured building some muscle might help me look less scrawny. It probably wouldn’t change much, but it was worth a shot.

After showering, I headed to the pool entrance, only to realize I’d forgotten my goggles. “Must’ve left them in the changing room,” I sighed. “It’s a pain after showering, but I’ll go back.” Reona and Riona weren’t at the meeting spot yet, so I figured I had time. I retrieved my goggles from my backpack and started back, but as I neared the entrance, I heard raised voices—a mix of guys and girls arguing.

“Like I’ve said a million times, we’re here with someone else,” Reona snapped. “Riona and I have zero interest in hanging out with you guys, so back off.”

“You’re getting annoying,” Riona added, her voice icy.

“Come on, it’s fine,” one of the guys said, his tone sleazy. “Ditch that guy and come with us. We’ll show you a good time, promise.”

“Yeah, any guy who keeps cute girls like you waiting isn’t worth your time,” the other chimed in.

It was clear Reona and Riona were being hit on by a couple of college-aged playboys, complete with bleached hair and multiple earlobe piercings. Normally, I’d steer clear of guys like that, but the two looked visibly uncomfortable, so I stepped in.

“Sorry, could you stop hitting on Reona and Riona?” I said, keeping my voice steady.

“Huh? Wait, this guy’s the one you’re waiting for?” one of them scoffed, sizing me up.

“No way, this lame dude?” the other laughed. “Gotta be some random guy playing hero, right?”

“Yeah, no chance a boring guy like this is their boyfriend,” the first added, smirking.

I ignored their taunts and took Reona and Riona’s hands, intending to walk past them to the pool entrance. But the guys blocked our path, refusing to let us through. They probably weren’t dumb enough to start a fight in a crowded place, but their persistence was grating.

“You can leave if you want, but don’t try taking these two hotties with you,” one of them said.

“Wait, hold up, is this guy’s back kinda gross?” the other said, circling behind me.

“Whoa, you’re right. Look at those scars, like he got stabbed or something. Don’t show us that nasty stuff,” the first added, mocking me.

A chill ran through me, as if the air around us had turned frigid. Reona’s voice cut through, sharp and furious. “…What did you just say? Did I hear you call Ryouya-kun’s back gross and dirty?”

“W-Well, it’s true, isn’t it? Right?” one of the guys stammered, wilting under her glare.

“Y-Yeah,” the other managed, but his bravado was crumbling.

Then they saw Riona’s expression and froze. Her face was as emotionless as ever, but her eyes held a dark, bottomless void, radiating a fear I couldn’t name. A small kid would probably burst into tears just meeting her gaze.

“The scars on Ryouya’s back are from when he risked his life to protect me and my sister,” Riona said, her voice low and unyielding. “No matter who you are, I will never forgive anyone who insults them.”

The two guys trembled, like prey cornered by a predator. I started worrying that Reona and Riona might actually do something, but thankfully, a burly male staff member, alerted by the commotion, stepped in. The playboys were escorted away, looking utterly defeated and offering no resistance.

“You two okay?” I asked, turning to them.

“Yup, as you can see, we’re fine,” Reona said, her usual brightness returning.

“Thanks, Ryouya,” Riona said softly. “I was happy you stepped in to help.”

In stark contrast to moments ago, they were back to their normal selves, as if the fury had never happened. One thing was crystal clear: I absolutely could not afford to make Reona and Riona angry. Especially Riona—her terrifying aura had been even more intense than Reona’s, outdoing the pressure I’d felt facing that mugger.

“That was a big hiccup, but let’s finally enjoy the pool together,” Reona said, clapping her hands.

“Yup, let’s have tons of fun today!” Riona agreed.

“Looking forward to it,” I said, relieved. The three of us walked side by side toward the poolside. After that spectacle, witnessed by plenty of onlookers, I doubted anyone else would dare hit on Reona and Riona. We did some warm-up stretches and eased into the pool, one foot at a time.

“The water’s nice and cool,” I said, feeling the tension melt away. “Feels great.”

“Totally, it’s perfect for a hot day like today,” Reona said, splashing lightly.

“Glad we came,” Riona added, a rare smile tugging at her lips.

We chatted like that, diving into the fun. The place was bustling with families and couples, and Tokyo Aqualand’s sprawling facilities meant we could easily spend hours here. By the way, there was a summer-only outdoor area, but it was small, with the indoor facilities making up about 80% of the complex.

“…Now that I think about it, this pool has two types of water slides, doesn’t it?” I said, glancing around.

“Yeah, there’s a long slide and a short slide,” Reona confirmed.

“Since we’re here, I wanna try both,” Riona said, her eyes lighting up.

Apparently, the short slide was faster than the long one, so preferences varied.

“It doesn’t look too crowded right now,” Reona said, peering toward the slides. “Wanna try the short slide?”

“Sure, I was getting kinda bored just swimming anyway,” I said.

“I’m in,” Riona nodded.

With that, we climbed out of the pool and headed toward the short slide together.

“I heard you get a lot of speed if you lie down while sliding,” Reona said, eyeing the short slide.

“Oh, then I’ll try lying down,” I replied, intrigued.

“I’ll slide normally,” Riona said. “What about you, Onee-chan?”

“Since it’s a rare chance, I’ll lie down too,” Reona decided.

We chatted as the line moved quickly. The short slide’s shorter distance and dual setup meant a fast turnover, so we didn’t wait long.

“Alright, here I go!” I called out, lying down.

“Have fun!” Reona cheered.

“I’ll be watching you from up here, Ryouya,” Riona added.

I zoomed down the slide, the rush of speed exhilarating. As Reona had said, it was insanely fast, and I hit the water in no time. Climbing out to the poolside, I waited for Reona’s turn. She came flying down on her back, but the moment she hit the pool, an unbelievable mishap struck.

“No way, seriously!?” I gasped.

The top half of Reona’s red bikini had come loose from the impact, floating away. Her face flushed bright red as she dove underwater, frantically searching for it. I jumped in to help, and luckily, we found it quickly. I handed it to her, averting my eyes.

“I never thought the strings would come undone,” Reona said, still flustered as she retied it. “I totally panicked. I’m sure I tied them tightly in the changing room.”

“Guess you can’t let your guard down,” I said. “Honestly, I didn’t expect you to freak out that much.”

“I’m a girl, so of course I’d panic in a situation like that!” she huffed.

“But you didn’t seem to care about changing in front of me before, right?” I pointed out. During our sleepover study session, both Reona and Riona had stripped down without a second thought, so I’d assumed they were just carefree.

“It’s totally different when a bunch of random people might see me!” Reona protested.

“Oh, got it,” I said, catching her meaning. It almost sounded like she wouldn’t mind if it was just me, but I wasn’t brave enough to push that topic.

“By the way, Ryouya-kun,” Reona said, her tone teasing, “did you see my chest just now?”

“…Nope, not a thing,” I said quickly.

“Not even a glimpse?”

“Nah, I was too flustered to look.”

Truthfully, I’d caught a fleeting glimpse, but admitting that risked a pervert label, so I kept my mouth shut. Riona came down the slide without incident, and the three of us headed to the jacuzzi.

“This is nice and warm,” I said, sinking into the bubbling water. “Feels great.”

“Yeah, it’s like all my recent stress is melting away,” Reona sighed contentedly.

“Ryouya, you sound like an old man,” Riona teased.

“You’ll understand when you’re my age, Reona and Riona,” I shot back, playing along.

“Come on, Ryouya-kun, we’re the same age!” Reona laughed.

We bantered playfully, the warm water easing the tension. Lately, events had been piling up so fast I’d collapse without moments like this. I’d had enough hospital stays after that mugger incident, and I wasn’t keen on repeating that anytime soon. After the jacuzzi, we floated along the lazy river and relaxed in the sauna together.

“…It’s been almost three hours since we started playing in the pool,” I noted, glancing at the clock.

“Time flew by so fast,” Reona said.

“That just shows how much fun we’re having,” Riona added.

While chatting, we lined up for the long slide. Learning from earlier, Reona and Riona had double-checked their bikini strings, so no repeats were likely.

“I’ll go first this time,” Riona said. “If Onee-chan’s bikini comes off again, I’ll look for it.”

“I told you, I’m fine this time!” Reona snapped. “Do you really have that little faith in me?”

“Onee-chan, you’ve always had a habit of repeating the same mistakes, so honestly, I don’t trust you,” Riona said bluntly.

“That’s kinda harsh, isn’t it?” Reona pouted.

I couldn’t help but laugh at their exchange, but Reona’s glare made me look away quickly. We kept chatting, and the line moved steadily until it was our turn.

“I’ll wait at the bottom,” Riona said, sliding down seated.

“My turn now,” Reona said.

“Make sure your bikini doesn’t come off this time,” I teased.

“Ugh, I get it, Ryouya-kun, you jerk,” she muttered, her face reddening as she recalled the incident. She slid down on her back, and thankfully, no mishaps this time.

After confirming Reona made it safely, I started sliding at the staff’s signal. I’d retied my swim trunks tightly, so I figured I was safe. But then, disaster struck.

“Crap!?” I yelped.

Halfway down, my right leg cramped, and when I hit the water, my left leg seized up too. Panicking, I floundered in the pool, unable to move properly.

“Ryouya!?” Riona shouted.

“Ryouya-kun!?” Reona called, her voice sharp with worry.

Their faces pale, they dove in and pulled me out quickly, preventing a bigger mess. I had to stop them with all my strength when they tried to give me mouth-to-mouth, my embarrassment outweighing my pain.

◇

The day after Tokyo Aqualand, I woke up with a sore throat, coughing, and crushing fatigue. Suspecting a cold, I grabbed a thermometer from my desk drawer and checked my temperature.

“…No way, it’s over 38 degrees,” I muttered, staring at the reading. Definitely a cold, probably from the pool yesterday.

Worried about Reona and Riona, I sent them a quick LIME message to check in. Then I shuffled to the dining room shelf for cold medicine, cooling sheets, and a mask. As I headed back to my room, my phone buzzed loudly in my pajama pocket. The screen showed Tsurugi Reona’s name.

“Hello…” I croaked.

“Ryouya-kun, you okay?” Reona asked, concern clear in her voice.

“Your voice sounds rougher than usual,” Riona added, her voice coming through on speakerphone.

“…I’ve got a fever over 38 degrees, so it’s pretty rough,” I admitted.

“That sounds tough,” Reona said. “Alright, Riona and I will come take care of you.”

“We’ll get ready and head to your place, so hang tight,” Riona added.

They were serious about coming over. Sure, I’d fantasized about being nursed by a beautiful girl, but making them go that far felt too guilt-inducing.

“I really appreciate the thought, but you might catch it, so I’m fine…” I protested weakly.

“But didn’t Mio-chan say yesterday she’d be out all morning?” Reona pointed out. “So you’re home alone, right, Ryouya-kun?”

“We can’t just leave you like that,” Riona said firmly.

“Alright, I’ll take you up on it then,” I relented. They weren’t backing down, and it seemed they’d show up whether I agreed or not.

Not long after, Reona and Riona arrived at my room with a plastic bag full of sports drinks. They must’ve left right after the call to get here so fast.

“Ryouya, you look awful,” Riona said, frowning. “No overdoing it today.”

“Yup, Riona and I will take good care of you, so don’t worry,” Reona added.

“Thanks, you’re lifesavers,” I said, my voice barely above a whisper. My body felt heavier than when I’d woken up, and their help was sinking in as a genuine relief.

“We’ll go make some porridge in the kitchen,” Reona said.

“Sorry for all the trouble,” I mumbled.

“Don’t worry about it,” Riona said. “We’re doing this because we want to.”

They left for the kitchen, and I dozed off on my bed, the fever dragging me under. When I came to, they were back with a tray.

“Ryouya-kun, sorry for the wait,” Reona said. “The porridge is ready.”

“It’s hot, so eat slowly,” Riona advised.

“Thanks, it looks delicious,” I said, picking up the spoon. But the fatigue made it feel like lifting a boulder, and I struggled to eat. Reona and Riona exchanged a glance, then said something outrageous.

“…Hey, Ryouya-kun, how about we feed you the porridge?” Reona suggested.

“No, that’s a bit much…” I protested, embarrassed.

“No need to hold back,” Riona said, already scooping up a spoonful.

At seventeen, being fed felt humiliating, but I knew from experience that stopping Reona and Riona once they were set on something was near impossible. I caved.

“…Alright, I’ll let you feed me,” I sighed.

“Good boy for being honest,” Reona said, smirking.

“Ryouya, open your mouth,” Riona instructed.

I took a bite of the porridge Riona offered. The gentle flavor spread through my mouth, comforting despite my condition.

“It’s good… but still a bit too hot to eat,” I said.

“I’ll cool it down more next time,” Riona said, blowing on the next spoonful alongside Reona. Their coordinated effort was oddly captivating, and to my horror, my lower half started getting a bit too lively. The blanket hid it, thankfully, but if they noticed, I’d be doomed. I focused on staying calm.

“It should be cool enough now,” Reona said.

“Ryouya, say ahh,” Riona prompted.

The porridge was perfect this time. We repeated the process until the bowl was empty.

“Oh, I heard that passing a cold to someone else makes it heal faster,” Reona said suddenly, her tone mischievous. “Wanna try?”

“…How, exactly?” I asked, wary.

“Colds spread through droplets when viruses stick to mucous membranes,” Riona explained matter-of-factly. “So, we just need to touch mucous membranes.”

“Which means if Ryouya-kun and us do a deep kiss, it’ll work for sure,” Reona added, grinning.

“No way, not happening,” I said, my fevered brain reeling. As if my condition needed that kind of chaos.

“Aww, I thought it was a brilliant idea,” Reona pouted.

“Let us know if you change your mind, Ryouya,” Riona said, handing me water and cold medicine.

I doubted I’d ever change my mind, but I kept that to myself. “Alright, Ryouya-kun,” Reona said, standing. “Take this and rest today. We’re heading out now.”

“Don’t push yourself,” Riona added. “Get well soon.”

“Thanks for everything today, you two,” I said sincerely.

After they left, I lay back, staring at the ceiling. Exhaustion pulled me under, and I drifted into a deep sleep. Thankfully, my cold cleared up by the next day, sparing me from wasting too much of my precious summer vacation.