Prologue

I have a girlfriend. A very, very cute one.

“It’s scorching… a total heat island effect.”

“Sounds like a fun resort phenomenon to me!” Yuki Aiba, walking beside me, chirped.

“A heat island isn’t a tropical vacation, you know,” I corrected.

This was on the way home from a date, far from our local neighborhood after school.

The countless cars rushing down the four-lane main street, the towering, densely packed buildings—all of it contributed to a legitimate heat island effect. What made it worse was the intense late-afternoon sun, still beating down with a vengeance even as it began to set in the west.

The air was thick and heavy, and sweat was already tracing a path down my back just from walking through the concrete jungle.

“It’s insane how hot it is, and we just started June. It’s too much for an indoor guy like me.”

“Let’s hurry up and get somewhere cool, like the station!”

Despite the miserable heat, Yuki’s amber ponytail bounced energetically with every step. Her chest strained against her white shirt, a surprising contrast to her youthful face, and her pale legs, stretching out from the gray miniskirt, were pleasantly shapely. She was also a girl who carried a faint, citrusy scent.

But I wasn't the only one paying attention to Yuki.

“Man, I was really looking forward to a Yuki concert~”

“You’ve been saying that ever since Yuki retired, haven’t you?”

The conversation from a couple of girls, who appeared to be from another school, drifted into my ears. Acrylic charms dangled from their school bags. They were of a moderately famous former idol called ‘Yuki,’ who was the spitting image of—no, the exact same person as—Yuki Aiba.

But the Yuki of today wore round glasses and had completely changed her look, so the people around us never seemed to realize she was the former idol.

“They were looking forward to my concert,” Yuki murmured, her eyebrows drooping apologetically.

“I feel bad that I disappointed them by retiring so suddenly. I wish I could at least give them an autograph, but…”

“I just think it’d make things harder on you, though.”

“…Yeah, you’re right. I wouldn’t even know what to say, since I’ve already retired.”

I spoke softly to Yuki, who looked like she was about to be crushed by her own sense of responsibility.

“You did more than enough, Yuki. You don’t have to overthink things.”

“Hehe, thanks. It makes me happy when Shinya praises me.”

Yuki’s cheeks flushed slightly, and she held out her small hand.

“Can we hold hands? I feel safe when I’m connected to you, Shinya.”

Yuki was a beautiful girl who would make anyone turn their head, and to be honest, holding her hand always made me nervous.

But Yuki liked to be close to me, and I wanted to see her happy. So, I said, “I want to hold your hand too,” and took it.

“Ehehe~ Thanks, Shinya.”

Her face went all mushy as she laced her fingers through mine—what people call the lover’s grip. Her fingers were slender and delicate, reminding me that she was, undeniably, a girl.

But Yuki’s ears were bright red. Even I, with my limited romantic experience, knew it wasn't just the heat.

“If you’re that embarrassed, maybe we don’t have to hold hands?”

“W-Well, you’re bright red too!”

“That’s because I’m not used to girls.”

“Wow, you just own that, huh?!”

The playful atmosphere shifted instantly, and Yuki’s voice became soft and moist.

“Then you can just get used to it with me.”

As she spoke, she squeezed the hand we were holding with a comfortable pressure.

“First love is the best, isn’t it?”

“I totally get that.”

“Just holding hands makes my heart pound.”

“We’ve done it plenty of times already, though.”

“But still! First love is special, after all.”

“That’s why,” Yuki said, her voice bubbling with excitement, and her steps became lighter with the momentum.

“Even the walk home from a date is fun!”

“Even with a plain-looking guy in glasses like me?”

“It’s fine because it’s you, Shinya.”

She clung to my arm playfully, and I couldn't help but feel her softness.

Though small, Yuki was well-developed, with a figure that was firm where it should be, but still possessed a distinctly feminine softness. As I became conscious of that through our uniforms—

It was right then, as I was thinking such impure thoughts.

“Eep!”

A sudden, strong gust of wind blew, causing Yuki’s skirt to flutter up. She frantically pushed it down, but not before I caught a glimpse of her soft, white thighs and a piece of alluring fabric underneath.

The wind stopped immediately, but Yuki stared intently at my face.

“…Did you look?”

“I looked. And I looked hard.”

They were very cute light blue and white stripes. A little childish, perhaps, but combined with Yuki’s youthful face, it was an exceptional combination.

“I know it was wrong, but at least let me offer a defense.”

“Defendant Hayasaki Shinya, I’ll allow your testimony!” Yuki said with a sharp expression, her acting skills honed from her time as an idol in TV dramas.

“Guys have a hunting instinct, so their eyes are drawn to things that move.”

“Speaking of things that move, does that include my ponytail?”

“Of course.”

“And my chest? Do you look at that a lot?”

“Ah, that is an instinct no man can resist.”

“Leave it to the Brain Psychology Research Society President~ Always trying to excuse yourself with a scientific-sounding explanation~”

“S-Sorry…”

“It’s fine. I kinda showed you on purpose anyway,” she said, giving me a mischievous smile.

“I’m honestly happy, but you shouldn’t be so defenseless…”

“But it makes me happy when Shinya looks at me a lot!”

Yuki gave a shy smile and hugged my arm tightly.

“You really never lie, Shinya. You could have just said you didn’t see my panties, y’know.”

“I never lie. It’s a promise I made to the girl I first fell in love with.”

“I love that about you, Shinya—that you never lie,” she said, smiling.

Just looking at the face of my adorable girlfriend warmed my heart.

◇◇◇

“I always figured the Health Committee was just a bunch of slackers, y’know.”

“Slacker or whatever, I’d still have fun if I was with Hayasaki-kun~”

“If Aiba-san says so, then fine by me.”

Hoshinomiya High School, the place we attended, was perfectly unremarkable.

It was a perfectly ordinary afternoon, fitting for an ordinary school. Yuki and I were walking down the corridor, the sound of light rain echoing against the windows, chatting idly. Having finished our Health Committee duties, we exited classroom 2-A, maintaining the distance of mere friends, not even holding hands.

“Hayasaki-kun, is that…”

Along with the quiet sound of the rain, the melody of a violin drifted into our ears.

The light, effortless movement of the bow was obvious just from the sound, delivering a gentle, flowing tune. It was a duet with the soft rain tapping on the window, like a concert exclusive to the rainy season.

As we reached the covered walkway, the sound became even clearer.

And there, at the center of the sound, was the girl playing. We stopped near her.

Flowing black hair, a perfectly sculpted face, and black tights covering long legs that stretched out from her skirt. Despite her well-developed figure, she gave a slender impression, thanks to her dignified, straight posture and her perfectly neat uniform.

Swaying gently like a drifting cloud, she carefully played each note of the light, pastoral melody, a scent as floral as her movements filling the air. She was a presence whose outline remained sharp even on a dull, rainy day, a girl who drew my gaze and held it: Sara Segawa.

Neither of us had the sophistication to truly appreciate the performance, but we both listened to the melody for a while.

When she finished, Segawa-san casually put her violin and bow back into the case.

In an instant, Yuki bolted straight toward Segawa-san.

“Sara~!”

She threw her arms around her and rubbed her cheek against her with a look of pure joy.

“Sara, you’re so cool when you play! I love you~!”

Yuki was like a small, playful animal. Segawa-san smiled and patted Yuki’s head, saying, “There, there.”

“Sorry about Aiba-san, she’s always a straight-line dog,” I said, following Yuki and speaking to Segawa-san. Yuki was totally smitten, saying, “I love Sara, woof!” and a part of me, despite myself, felt a pang of jealousy at their girl-on-girl affection.

We’d been in the same class since first year, and we were always a trio like this.

“I may not have a leash, but shall we walk home together?” Segawa-san offered.

“Woof!” Yuki barked.

As the three of us headed from the covered walkway to the shoe lockers, the rain was still drizzling.

Segawa-san, who always checked the weather, had an umbrella, and I opened my foldable one.

“Sara~ Let’s share!”

Having apparently forgotten her own umbrella, Yuki slipped under Segawa-san’s and clung to her arm. I walked beside them, secretly grinding my teeth at the sight. The pleasant vibration of the raindrops hitting my umbrella was transmitted through the handle.

“Still,” I commented as we walked along the tree-lined path.

“Segawa-san and Aiba-san look like a couple.”

“Hehehe~ Jealous, are we?” Yuki teased.

“I’ve been grinding my teeth so hard they broke from jealousy.”

Segawa-san, deadpan, replied, “If it’s a bottom tooth, you should throw it onto the roof.” Her sense of comedic timing was wildly off.

“Wait, but Sara~ Why were you playing the violin on the covered walkway?” Yuki asked.

“If I do that, you two will know exactly where I am, won’t you? Then we can go home together right away.”

“I see! Sara, you’re so smart~!”

“Uh, couldn’t you have just texted us…?”

Yes, Segawa-san was a little airheaded.

In a way, she and the slightly ditzy Yuki were a good match.

But if I left them alone, their conversation would veer off in all sorts of strange directions, so I often had to play the straight man.

As we walked home in our usual fashion, Yuki pulled a bar of chocolate from her school bag and broke it into three equal pieces. We ate it as we walked, which livened up the conversation.

“Mmm~ Something sweet really hits the spot when your brain’s tired from studying~”

“Aiba-san, you were asleep during class.”

“No, no! It was sixth period math! I think that’s totally excusable!”

Yuki was the type who could focus intensely on things she liked, but was utterly useless at things she didn’t. Segawa-san frowned at her, looking concerned.

“Are you going to be okay for the next test, then?”

“Doesn’t look like it! I have a feeling I’m gonna fail the finals!”

“In that case, how about a study session?”

“Ugh, studying… But I do have time since I quit being an idol, so maybe I’ll do it!”

“Even if we hold a study session, Aiba-san won’t be able to focus for long.”

“Waaah~ Sara~! Hayasaki-kun is bullying me~!” Yuki wailed, clinging to Segawa-san’s arm in mock tears.

Segawa-san gave a wry smile and replied, “Well, well, it’s the truth, so you can’t help it.”

“Waaaaaah! I’m doing an unsupported handstand!”

“You mean you’re helpless and alone.”

Doing a handstand in the middle of the street was just being a weirdo.

While we were laughing, we reached the crossroads that branched off into the residential area.

Segawa-san’s route continued straight toward the station. She had a violin lesson and was apparently going straight home.

“Well then,” she said.

Her voice was monotone, but she gave us a small wave, and we waved back. It was just as we turned into the residential area.

“Excuse me for intruding~”

After confirming no one was around, Yuki ducked under my umbrella. She pulled the umbrella down low, hiding our faces. The space was closed off, and Yuki was close. Too close.

“Hey, hey, since we’re here, let’s get a little closer!”

“I think we’re already pretty much pressed up against each other, though…”

“We can do better! Don’t limit yourself! You can do it if you try!”

“I don’t need a pep talk from a hot-blooded tennis player…”

Yuki was unusually energetic today.

“Shinya, you really need to get more used to girls.”

“Well, I can’t argue with that…”

“So, why don’t you pull me closer? That’ll be practice for getting used to girls, right?”

“O-Okay, if you insist…”

I put the hand not holding the umbrella around Yuki’s shoulder and pulled her in. She rested her head on my shoulder. Instantly, the citrus scent wafted up. It was Yuki’s scent, which I loved.

“Girls are creatures that love it when the guy they like does this,” she said.

Seeing Yuki’s adorable smile lifted my own mood.

“Speaking of which, Shinya, you were reading a book all by yourself this morning, weren’t you?”

“My one or two friends got called out by a teacher.”

Yuki was chatting with her girlfriends, and Segawa-san was silently reading. So, I, who didn’t have many friends, was left with no choice but to read or look at my phone.

There was a reason for this isolation. Before high school started, I missed the group that made friends using the ‘#SpringFromHoshinomiyaHigh’ hashtag on social media, and I was completely left behind. As a result, even in my second year, I only had deep connections with a handful of people, including Yuki and Segawa-san.

“But it’s okay! Whenever you’re lonely, I’ll comfort you as much as you need!”

“You’re still awfully hyped up, aren’t you?”

“Ehehe, because sharing an umbrella with Shinya makes me happy!”

Yuki was a former idol, and for various reasons, we were dating in secret.

That’s why I called her Aiba-san at school, and she usually referred to me by my last name, Hayasaki-kun.

Our secret relationship might look like I was lying to everyone around us.

But this was a secret. I didn’t lie, but I did hide things. It didn’t violate the promise I made to my first love: I will never lie.

“Ugh, I wish we could be like this at school, too.”

“If we did that, everyone would find out.”

But I needed to find more ways for Yuki to disguise herself besides the round glasses, or someone might figure out our relationship.

What should we do? We joked about it, having a good laugh.

“How about you try wearing plain, square glasses like mine? It’d change your impression.”

My glasses were square-framed, a little dorky, unlike Yuki’s cute ones.

“I want Shinya to think I’m cute, so I don’t know about those glasses~”

Despite her words, Yuki snatched my glasses, put them on, and smiled smugly.

“Since I have them, can I take a selfie? A souvenir for stealing Shinya’s glasses!”

“Sure, I guess. Whatever you want.”

Yuki held up her smartphone and snapped a picture. “Hold on a sec,” she said, stopping, and with practiced ease, launched an app and started editing the photo.

She handed my glasses back and showed me the phone with a beaming smile.

“Done! Don’t I look pretty great?”

The photo she showed me was excessively bright and pale, and her eyes were heavily edited to be large and sparkling. It also had the word ‘SUMER’ written on it, which meant Sumer. We weren't in Mesopotamia. It was probably a mistake for ‘SUMMER’…

But there was one other thing that bothered me.

“Isn’t it a little too sparkly?”

“Girls have a habit of collecting sparkly things~”

“Are you a crow?”

“It’s a high school girl’s hobby! Caw-caw!”

Yuki flapped her hands and imitated a crow’s cry.

As we exchanged jokes, our conversation gradually quieted down.

We were getting close to my house, which was near Yuki’s apartment.

“Hey…”

The high energy from earlier was completely gone from Yuki’s voice. It was softer than the rain, gently stirring my eardrums.

“I have quite a bit of time today.”

She said this, her cheeks flushed, giving me a hesitant look.

“Is anyone home at your place, Shinya?”

“No, it’s just me.”

“Good,” Yuki said, her voice brightening.

“Then, let’s go and… get close, just between us?”

We entered my home, a typical twenty-year-old apartment complex, and headed to my room on the second floor.

Yuki gave a wry smile at the sight of my slightly messy room but didn't say anything, instead sitting down on the bed.

Only the sound of the rain outside the window echoed in the enclosed, intimate space.

“A girl shouldn’t be so casual about…”

“But that’s what I came here for. You were hoping for it too, weren’t you, Shinya?”

She was right. Sometimes, we spent time together in my room like this.

Since our relationship couldn't be public, we sometimes had ‘house dates’ out of sight.

“Come on, over here.”

Yuki spread her arms and beckoned me. I was drawn in, burying my face in her chest.

The citrus scent and the soft sensation of her body made my consciousness sink. My thoughts dulled.

The quiet rain, the space where time seemed to stop. My heart was captivated by the feeling, which I hadn't experienced in days.

After holding each other for a while in silence, Yuki smiled.

“You’re such a baby.”

“I’m just a little tired.”

“It’s okay. Let’s just stay like this for a while.”

Yuki gently stroked my head.

“Sorry, I’m always the one leaning on you.”

“Then, in return, I want you to do the usual.”

When she said that, I lifted my face from her chest and gently stroked her head. She closed her eyes blissfully.

It wasn't her idol smile. This was the real Yuki Aiba, the one she only showed to me.

We continued to just hold each other, but then Yuki guided my hand to her thigh.

“Is this… okay?” I asked.

“It’s been a month since we started this relationship. I want you to take things a little further.”

Despite her words, Yuki’s body was tense and stiff.

Of course. It must take incredible courage for a girl to initiate something with a guy.

And the reason she had to do this was because I had never taken the initiative with her.

So, hesitantly, I gently stroked her thigh.

“Ah, nnh…”

Yuki let out a soft sound and twitched.

“I-It’s okay,” she insisted when my hand paused, urging me to continue. I continued to stroke her thigh.

Her leg, completely smooth, was firm, and touching it with my fingers offered a soft, cushiony sensation. My hand, chilled by the rain, gradually warmed up from Yuki’s body heat, which felt wonderfully comfortable.

Lost in the novel sensation, Yuki guided my other hand as well.

“I want you to touch this side, too.”

In a pleading tone, she moved my hand to her chest. My touch was tentative, fearful. Her eyes fluttered, half-expectant, half-anxious.

“I-Isn’t this too fast? You don’t have to force yourself…”

“I’m not forcing myself. This is what I really want. That’s why I want you to touch me. I want you to feel me.”

I couldn’t refuse a request like that.

I stroked Yuki’s thigh with my left hand while touching her chest with my right.

The sensation through her white shirt was incredibly soft. My fingers sank in and were pushed back, like touching a water balloon.

Was that firm fabric her bra? I traced the outline of Yuki Aiba, with that layer included.

I became completely engrossed in touching a girl’s body for the first time. I hadn’t known that the girl I spent time with every day was something so soft and sweet.

“Hah, nnn… Sh-Shinya…”

Every sweet sound Yuki let out made my brain go haywire. Yuki’s adorable face, the feel of her skin, her scent, her moans. I was experiencing her using nearly all five senses.

“Sh-Shinya, more, more…”

Yuki stuck out her tongue, pleading.

From here, it was an even more unknown territory. And the last of the five senses: taste.

If we pressed our lips together and devoured each other, my head would go even more blank. I would be intoxicated by that sweet flavor. If we intertwined our tongues and made sounds loud enough to drown out the rain, we would rush headlong into something irreversible. But—

“I can’t do that.”

I refused.

“O-Oh, right. I knew that.”

And Yuki understood.

“We have a rule not to kiss.”