湯けむりと混浴と…心拍数。Yukemuri to Konyoku to... Shinpaku-sū.

Steam, Mixed Bathing… and Elevated Heart Rates.

A trip to the hot springs was not in Ren's mental planner this week.Not after confessing his feelings to Emi.Not after seeing Haruka's cold eyes.Not after Yui's silent retreat.Not after Mei had rested her head on his shoulder like she was quietly saying goodbye.

But when the school's cultural committee announced an "overnight hot spring relaxation trip" to relieve student stress…

The girls immediately signed everyone up.

Well, except Ren.

He found out when he opened the group chat and saw:

Rika: Hot springs. Mixed bath. Bring extra underwear. No questions.

Yui: ...Please ignore her.

Mei: Pack modest towels.

Emi: We're all going. Please come.

Haruka: If you don't want me seeing you naked, bring a swimsuit.

And that was how he found himself standing at the wooden gates of a traditional ryokan, trying very hard not to imagine how many ways this weekend could go wrong.

Dinner was suspiciously peaceful.Everyone was polite. Quiet. No chopstick battles. No food stealing. Not even Yui biting into her fish headfirst.

The tension wasn't as sharp anymore — it had turned mellow, like the warm lighting of the tatami hall they were seated in. But the undercurrent was still there.

Emi kept glancing toward Ren and looking away.Haruka pretended to not be looking.Yui didn't speak at all.Rika kicked him under the table. Twice.Mei? She was calmly pouring tea, as always.

And then the owner of the ryokan walked in and ruined everything.

"Baths are now open," he announced. "Our outdoor onsen is fully co-ed tonight."

Silence.

Then—

"…Co-ed?" Ren whispered.

Haruka sipped her miso soup. "Didn't you bring that swimsuit like I told you?"

"I thought you were joking!"

Yui stood up immediately. "I'm going in first. Don't even think about peeking."

Rika stood up second. "I'm going in with her to make sure she doesn't peek at you."

"…What?" Ren blinked.

Mei stood up third. "I'm going to make sure no one dies."

Emi stood up last, adjusting her yukata. "Ren, if you're too nervous, I can wait and go with you…"

That sentence alone nearly gave Ren a heart attack.

The hot spring water was perfect. Too perfect. The kind that made you forget your name and morals after two minutes.

Ren submerged halfway, towel draped over his head, trying not to think about the fact that somewhere — just over the rock wall behind him — were five girls who had all at some point thought about kissing him.

And one of them had.

Voices echoed faintly from the other side.

"Don't splash me, Rika!"

"Stop staring, Yui!"

"I'm not staring! This is how I naturally turn my head!!"

"Please lower your volume," Mei's voice floated in calmly.

Ren tilted his head back against the rock and groaned.

And that's when the splash came.

He looked down.

Someone had just climbed into his side of the bath.

Wet hair. Slender shoulders. Steam curling around a bare collarbone.

"Y-You're on the wrong side—!" he stammered.

"Shh." Rika held a finger to her lips. "I told them I needed to pee."

"YOU WHAT—?!"

She slid closer, ignoring his panic.

"You kissed Emi, huh?"

Ren went stiff.

"I heard it from Yui. Don't worry, I'm not mad."

She leaned closer, lips dangerously near his ear.

"I'm just reminding you… the game's not over."

And then—

SPLASH.

Another body hit the water. Followed by another. And another.

Suddenly the rock wall behind him was way too crowded.

"What the hell, Rika?!" Yui yelled, water streaming down her hair. "You said you were going to the toilet!"

"I was. Then I changed my mind."

"Mei said it was okay," Haruka added calmly, adjusting the towel on her chest.

Emi walked in last, holding a second towel in front of her.

Ren's brain blue-screened.

The five of them surrounded him in the bath — each at varying distances.

He sank lower into the water, face red, heartbeat climbing like a rollercoaster.

This wasn't how mixed baths were supposed to go.

This wasn't how sanity survived.

"Um… nice weather today," he mumbled.

Rika smirked.Yui sighed.Haruka crossed her arms under her chest — which only made things worse.Mei smiled.And Emi… quietly leaned her shoulder against his.

And just like that…

Ren's heartbeat spiked again.