Mash-Up: I'm Not A Substitute

The Kobe Maritime Museum was a large-scale venue themed around "sea, ship, and port." It was one of the most iconic landmarks in Kobe.

At the entrance stood a boy in trendy, high-end fashion, looking like he'd stepped out of a magazine.

He was handsome—even just standing there doing nothing attracted the gaze of many girls passing by.

He seemed to be waiting for someone. He politely turned down all the girls who came to chat him up.

"Sorry, Makabe! I'm late. You've been waiting long, haven't you?"

After who knows how many girls he'd refused, Adagaki Aki walked out from the ticket gate and approached.

The boy—no, Makabe Masamune—smiled at her. "It's fine. I just got here too."

"Good, I was worried you waited too long."

"It was my pleasure."

"Jeez."

They entered the museum together, watched clownfish through the safety glass, sat in the front row of the dolphin show and got soaked, and later had a lovely meal while chatting about marine life.

At the end of the happy date, when they were parting ways, Adagaki Aki shyly looked up at him.

"Thank you for today, Makabe. I had a great time."

"Me too."

"Umm… I know I've said a lot of mean things to you before, and I'm really sorry. Actually… I really like you."

Her eyes were full of hope.

He smiled and whispered in her ear, "Who would like someone like you?"

Then, watching Adagaki Aki fall to her knees in despair, shedding pearl-like tears, Makabe Masamune laughed mercilessly.

——That was just Sheepy's fantasy time.

"…Why are you just standing there grinning like an idiot?"

Makabe Masamune snapped out of his Eternal Mangekyō Sharingan illusion just as Adagaki Aki's annoying voice yanked him back to reality.

He opened his eyes, about to show the charming smile he had practiced countless times in the mirror.

His mouth had just started to curl—

But then… he froze.

Because standing next to the doll-like adorable Adagaki Aki—

Was a man.

And the man wasn't worse-looking than him. Okay, maybe even better-looking, dammit.

Height… Makabe Masamune tried comparing.

He even stood on tiptoe—and still came up short.

What the hell!?

Why does a guy have to be that tall!?

It's okay, I've got a great physique. That boyish pretty boy can't match me—

But then his gaze shifted to the man's figure, and his confidence shattered.

The man wore a high-end white suit that fit perfectly. Broad shoulders, narrow waist, long legs—he looked like a towering mountain.

It was the first time Makabe had met someone his age who beat him in looks, height, and build.

And the guy was with Aki.

What the hell is going on between them!?

Until now, no one had ever posed a threat to him. Makabe had always been confident Aki wouldn't fall for someone else.

But now, facing an equal-tier rival, he started to panic.

"Adagaki-san, who's this?"

"Oh, I forgot to introduce him!"

Adagaki Aki playfully tapped her head and stuck out her tongue. 

Then she sweetly wrapped her arms around Takashi's arm, resting her head on his shoulder.

"Makabe-kun, this is my boyfriend—Takashi."

Takashi glanced at Makabe, then at Aki, and instantly understood why she'd suddenly invited him out, bought him clothes.

So that's it… she's using me as a shield!

Got it!

Takashi snapped into role instantly, grasped Makabe's hand with both of his, and said:

"So you're Makabe-kun. I've heard a lot about you lately from Aki."

"Thanks for taking care of her at school."

"Aki's got a temper and speaks without thinking. She can easily offend people. I'm worried when I'm not around her."

As he spoke, he looked down at Aki with a helpless yet affectionate expression.

"Damn, you sound so convincing I almost believed you myself."

Adagaki Aki shot him a glare.

This guy lies as easily as breathing. Doesn't even need a script?

"Who's the one refusing to transfer schools?"

Aki picked up the thread and added with a pout.

"Fine, fine, it's all my fault."

"It is your fault! You insisted on staying at Aoba and wouldn't transfer to Shinkawa!"

"What's so great about Shinkawa?"

"Are you saying coming to Shinkawa with me would've been a burden?"

Makabe watched the two bickering sweetly, his heart feeling like it was being stabbed by cold needles. 

He could hardly breathe.

He just wanted to find a quiet place to sit alone and wallow in his misery.

"…Alright, not in front of others. I'll go kneel on durians when we get back, okay?"

Takashi lowered his voice on purpose—but not low enough. Makabe still heard it, and it cut deep.

"So I'm… an outsider now?"

What about all those memories we shared since childhood?

Makabe wanted to question Aki—but he couldn't.

He was afraid that if she found out who he really was, she'd laugh even harder.

That woman was so cruel. Such a monster!

How was he supposed to keep pursuing his revenge like this?

Makabe calmed himself, forced a smile. "Let's go inside."

"Excuse us."

Takashi smiled politely. "By the way, Makabe-kun, how much were the tickets for Aki and me? I'll pay you back."

"No need, it's just a small amount."

"But it's still your parents' money. I can't let you pay for us."

As if you aren't using your parents' money too! (Takashi: I use women's money!)

Makabe fumed inside. He sensed Takashi was throwing shade—but wasn't sure if he was overthinking it.

"It's 4800 yen total. Just give me 4000."

"What? No way. I'll pay the full price—every last yen."

Takashi pulled out four 1,000 yen bills, a 500 yen coin, and three 100 yen coins, and handed them to Makabe.

Makabe stared down at the money in his hand and somehow just… felt disgusted.

"Alright, let's go."

Makabe shoved the money into his pocket, took a deep breath, and led the way into the museum.

He walked ahead, with Takashi and Aki trailing behind.

"…Seriously though, what's your deal with that guy?"

Takashi leaned in close and whispered in Adagaki Aki's ear, making it tickle. She instinctively shrank her neck, clearly ticklish.

So her ears are a weak spot, huh?

Takashi mentally noted that—never know when that could come in handy.

A qualified playboy should memorize every little detail about a girl.

"He's just one of my pursuers. He's been pestering me lately, no matter how I try to shake him off. It's driving me crazy!"

She honestly couldn't stand men.

Even if Takashi stood before her with all ten points in charm and looked like the peak of human aesthetics, she only felt he wasn't unpleasant—not that she actually liked him.

Let alone someone like Makabe Masamune, who was far inferior to Takashi.

Makabe kept bothering her endlessly, which was why she'd turned to Takashi for help.

Though Adagaki Aki refused to admit it, the only guy she could actually talk to right now was Takashi, pretending to be her boyfriend.

So she had no choice but to ask him.

"Help me deal with him."

"What's in it for me, Ojou-sama?"

Takashi saw a chance to profit and pounced.

"I already gave you something, didn't I?"

Adagaki Aki widened her beautiful eyes.

"That million was hush money. This date? That's extra!"

Takashi was firm about keeping things separate.

"I bought you so many outfits! You're literally wearing something I paid for right now!"

Adagaki Aki was getting a full taste of Takashi's shameless greed.

"Did I ask you to buy me those?" he retorted confidently.

"You—!"

Adagaki Aki had never met someone so brazen!

"Then take the clothes off!"

"Fine, I'll take them off."

Takashi didn't hesitate and immediately started unbuttoning his shirt right in front of her.

In no time, he was down to the last two buttons. His broad chest and well-defined abs were fully visible—enough to make anyone want to reach out and touch.

So this… is a man's body?

Adagaki Aki's cheeks flushed bright red.

It wasn't until Takashi undid the last buttons and started pulling the shirt off that she panicked and yanked him back.

For once, the usually bossy rich girl's tone sounded almost pleading:

"Please, I'm begging you. Put it back on."

She couldn't afford to lose face like this.

Adagaki Aki finally understood what it felt like when a trash-talking girl met a guy who was all too real.

"Miss Adagaki, surely you don't want me to keep stripping, right? At this rate, the Adagaki family's reputation is gonna crash and burn."

Takashi didn't care about shame, but Adagaki Aki definitely did.

"Fine! Take it!"

Faced with a shameless Takashi, she had no other choice.

"Thanks, Ojou-sama."

Takashi grinned as he began to dress again.

They entered the next exhibit: the aquarium.

Inside, the blue-white lighting turned the walls and ceiling into a scene straight from the deep sea.

Cylindrical tanks, reminiscent of sci-fi gene labs, housed jellyfish drifting like dandelions.

Their translucent bodies shimmered in different colors under the changing lights—truly a breathtaking sight.

Even Adagaki Aki couldn't help but stop and snap a few pictures with her phone.

After the aquarium, they walked beneath a massive marine tank, into a twenty-meter-long "undersea tunnel."

Schools of fish danced above and around them—darting quickly at times, freezing still at others.

Every shift in direction sent shimmering colors rippling across their scales like a living kaleidoscope.

"What kind of fish is that?"

Adagaki Aki pointed at a brightly colored fish with a diamond or oval-shaped body.

Before Makabe could respond, Takashi spoke up:

"Butterflyfish. Also called Chaetodontidae. They're found in tropical and warm temperate coral reefs across the Atlantic, Indian, and Pacific Oceans—mostly in the South China Sea, though some…"

"How do you know that?"

Adagaki Aki asked in surprise.

There were no info signs nearby.

"This kind of knowledge… shouldn't it come to us naturally as we grow up—like the powers in Dragon Raja?"

Truth was, Takashi only remembered it because he had crammed info with Utaha last time.

"What about this one?"

Adagaki Aki pointed at another fish, skeptical.

Takashi glanced. "Swordtail fish. Native to the rivers of Mexico and Guatemala…"

"And this?"

"Discus fish. Known for their unique shape and vivid patterns, they're top-tier ornamental tropical fish."

"This one?"

"Pearl cichlid…"

All along the tunnel, Adagaki Aki kept asking, and Takashi knew every single fish.

"You're… surprisingly impressive."

Trashy as he was, he really did know a lot.

"How do you think I ranked third in the entire country?" Takashi said smugly.

Adagaki Aki rolled her eyes.

Meanwhile, Makabe Masamune's mood grew darker.

Good looks, great body—fine. But now he's also better at school?

How the hell was he supposed to compete?

Takashi noticed the gloomy look in Makabe's eyes and smirked slightly.

He'd long known that while Makabe might look good and outperform Aki Tomoya academically by a mile, he was deeply insecure.

Just like some pitiful guy he used to know.

No matter how his outside changed, his core was always fragile.

So how do you handle a rival like this?

Caesar: "Watch closely, this is the only time I'll teach you!"

You don't even need to target him on purpose—just act normal. The rest takes care of itself. Makabe will crumble on his own.

Because they weren't even on the same level.

It was like asking a seasoned playboy to compete with a romance-starved high school newbie—this game was rigged from the start.

Most importantly, Adagaki Aki was now like Nono. In her eyes, Makabe Masamune didn't even exist.

The trio passed through the tunnel and arrived at the dolphin show arena.

It was the aquarium's most popular attraction. Aside from the front row, every seat was packed.

By the time they arrived, only the front row was available, so the three of them sat there.

"Why isn't anyone sitting in the front row?"

Adagaki Aki now treated Takashi like Doraemon—she asked without thinking.

"You'll see."

Takashi smiled mysteriously and said nothing more.

"So cryptic,"

Adagaki Aki muttered, but didn't press further. She settled in to enjoy the show.

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Sorry I didn't know who this Nono is. And no, it's not a typo for Nino.

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