After a brief conversation between Rias and Yasaka, the latter offered them a place to stay. Rias initially wanted to refuse—out of pride or perhaps caution—but Issei insisted. Ultimately, they accepted the hospitality.
Once they were gathered in a room—Yasaka excluded as the host—Rias immediately punished Issei by sitting on his back while he knelt on the floor like a bench.
It may not have looked like much of a punishment, judging by the perverted grin on his face, but devils were Sinful beings after all. Kousuke gave him a thumbs-up in solidarity when he saw it.
"You're awfully close to that Youkai," Rias said, eyes sharp and penetrating. Her tone suggested she thought he might be playing around behind Tsubaki's back—and she wasn't entirely wrong. Despite the rivalry between her and Sona, Rias still considered her a friend. That sentiment extended to her peerage as well.
Kousuke shook his head, a melancholic smile surfacing on his face.
"She just… reminded me of someone I used to know," he said quietly. That was all.
Still, guilt crept onto his face as he scratched his cheek. "Though I'll admit, I might've enjoyed immersing myself in her fluffy tails a tad more than I expected."
"While I can relate to a certain extent—I mean, they did look fluffy—but! You shouldn't be playing around with other women. Or I'll snitch to Tsubaki!" Rias warned, puffing out her chest proudly. She hadn't seen Tsubaki this madly in love before, and she felt protective—hoping her friend's first love wouldn't end in heartbreak.
"Funny you say that, considering Issei's whole shtick is wanting to be a harem king," Kousuke replied with a teasing smile. Beneath Rias, the 'chair' trembled at the mention.
Kousuke never intended to mess around with anyone else since becoming one with Tsubaki. He considered himself loyal boyfriend material. Still, just for a moment… he couldn't help but feel a flicker of temptation toward his friend's outrageous dream.
"T-That's different!"
"For a devil known for sin, you're surprisingly innocent when it comes to relationships," Kousuke quipped, then his smile faded as sincerity returned to his voice.
"But don't worry. I don't plan on hurting Tsubaki. She'll always have a place in my heart."
"Now and forever," he said firmly.
Rias couldn't meet his gaze. For some reason, she was overwhelmed by the weight of his devotion. His words struck a chord—because there was some truth in them. Devils, in general, had favorable views toward polyamorous relationships. There was one reason behind that: the low birth rate. If that problem didn't exist, she would've done everything in her power to keep Issei's harem dream from becoming reality.
Tsubaki might be upset at him for a while. She had been human once, after all. But if she learned just how difficult it was for devils to conceive children, she might eventually be forced to accept that unforgiving reality.
Of course, Kousuke never wanted things to end up that way. He planned to be honest with her the next time they met in Kuoh.
After all, there was no way she'd come all the way here to meet him, right?
At least, that's what he thought.
---
The next morning...
"Do you have something to say to me?"
There she was—the first thing he saw when he opened his eyes.
Tsubaki stood quietly next to the bed, her presence serene but heavy with expectation. He had woken up to the sound of her approaching footsteps.
Strangely, he wasn't surprised. He assumed Rias had told her, just like she said she would. He wasn't upset—if anything, he was grateful. He had been given the chance to explain himself.
"I'm sorry for being a scum," he said, sitting upright on his knees on the bed. He didn't dare meet her eyes—too afraid of what he might see.
"I… I didn't know Yasaka shared so many traits with my companion from when I was a Hero in the Other World."
"…Continue."
"When I saw her, I really thought I was hallucinating. After all… she died in my hands."
His fists clenched at the memory. It still haunted him. The pain of that loss would never truly fade.
"I'm sorry to hear that," Tsubaki said softly, "but let me ask you one thing."
"Who was she to you?"
"…My trusted companion," he admitted after a long pause. "And… my first love."
Silence followed—save for the sound of their breathing. He was calm on the surface, but tension lingered in the air.
Then she spoke again.
"I heard from Rias about the devils' problem before I came here. It was shocking—but it made sense. Nothing's happened since… after what we did."
He felt the mattress shift as she moved beside him. Her hand reached out and gently rested on his, her fingers caressing his skin with deliberate care.
"Do you still love me?"
"I do," he answered without hesitation. His eyes rose to meet hers—and what he saw wasn't pain or betrayal.
It was love.
Pure, unwavering love.
She smiled. "You know… I thought Issei was a playboy when I first heard he wanted to be a harem king."
"But Rias didn't think so. She truly believed that if he still loved her, it wouldn't matter if he had two or ten other girls—so long as she remained his first. His one."
"It sounded sweet, but I thought she was stupid. Naive, even. But now… maybe that's what she wanted to believe. In the end, it's up to Issei—whether to disappoint her or prove his love through his actions."
"So…" Tsubaki paused, then slowly intertwined her fingers with his.
"I will believe in you."
"It hurts to imagine you with someone else. But it would hurt even more to lose my first love to heartbreak. I might be as foolish as Rias, but I—"
He didn't let her finish.
He'd heard enough.
He showed her his answer through action—pressing his lips to hers in a kiss that was soft at first… but quickly deepened into something more.
"I locked the door," Tsubaki whispered between gasps once their lips parted, her cheeks flushed. She was prepared.
Kousuke smiled and gently cupped her cheek. "Then should we get busy?"
"Ahn~ b-but… what if they hear us?"
"Then, my love," he whispered, voice low and teasing, "you'll just have to keep quiet."
He turned her over, her back pressing against the bed. That mischievous glint was in his eyes again—one she recognized well.
It was the same look he wore the first night they shared together.
"Mmm… I'll try my best."
As he leaned closer to her face, he could feel his heart pounding—fast and wild. She seemed to share the same rhythm.
"I love you."
"I love you too~"
And so began another eventful morning.