Riko immediately snapped, her face turning red.
"A-a little sister?! Y-you don't even know which one of us is older!"
Yuuto turned toward her with a relaxed expression, the corner of his lips lifting.
"Oh?" he said lightly. "So Riko-chan doesn't want to be my little sister?"
"Or maybe you'd rather be my older sister? I don't mind either way—whichever you choose."
Riko's face grew even redder, all the way to her ears.
"Y-you…" she said, her words trailing off as she lost what to say.
"Hahaha," Yuuto chuckled softly at her reaction. He then turned his gaze toward Mikan.
"In that case, how about you, Mikan-chan?" he asked casually.
"You can't be my older sister, you know."
Mikan didn't answer. She simply turned her face away, pretending to be busy with the plate in front of her.
Yuuto raised an eyebrow, then smiled faintly.
"Oh… don't tell me Mikan-chan hates me?" he said half-jokingly.
"If that's the case, your big brother's feelings might get hurt, you know."
From the corner of his eye, Yuuto caught a faint redness on Mikan's ears—a small detail that made his smile widen, though he chose not to tease her any further.
What he's doing clearly isn't the kind of relationship siblings have… Mikan thought as she took a sip of the tea Belfast had made. Her eyes suddenly widened.
"Wow… this tea is really delicious," she said honestly.
"The ingredients are simple, but it tastes this good."
Belfast smiled gently at the compliment.
"I'm glad you like it, Mikan," Belfast replied warmly.
Yuuto looked at Mikan, who seemed genuinely enthusiastic while enjoying Belfast's tea, then said casually,
"If you want, Belfast can teach you how to make it."
"Eh, really? Is that okay?" Mikan asked as she turned toward Belfast, her eyes sparkling.
Belfast smiled and nodded lightly.
"Of course. I don't mind at all. I'll teach you later at home, darling."
Riko, whose face was still flushed, finally spoke hesitantly.
"Um… sorry if this is rude, but… what exactly is your relationship with Belfast?" she asked quietly.
Yuuto glanced at Riko, then smiled faintly.
"Oh? Curious?" he said casually. "What do you think?"
Riko lowered her head for a moment, then raised her face again with an awkward expression.
"Well… Belfast keeps calling you 'darling,' so I was thinking… m-maybe… you two are a couple?" she said haltingly.
"Hehe~ you're exactly right," Yuuto said with a smile. He casually wrapped an arm around Belfast's shoulders, completely at ease.
"We're a couple," he continued, then added lightly,
"and we live together."
"A-a couple… a-and living together?!"
Riko's face turned red again as her thoughts immediately ran wild. She quickly turned her face away, clearly flustered as she tried to suppress the images forming in her mind.
Beside her, Mikan also looked awkward. She chose to drink her tea a little faster than usual, hoping the warmth would calm her thoughts.
Yuuto observed both of their reactions and chose to remain silent for a moment, giving the atmosphere time to settle.
Only after a short while did he continue, his tone more relaxed.
"From now on, I'll be the one taking care of you," Yuuto said, alternating his gaze between Mikan and Riko.
"If anything happens or you need help, contact me right away. You both have my phone number, right?"
The two of them nodded lightly.
Yuuto then continued,
"Besides the cake earlier, I also have a gift for you."
He reached into his jacket pocket and took out two bracelets, handing them over carefully.
"I don't really know much about women's tastes," he said honestly with a small smile,
"but I hope you like them."
"Wow, the bracelet is really pretty," Riko said, her eyes shining as she accepted it.
Mikan stared at the bracelet in her hand, her eyes widening slightly.
"This is too nice… it must be very expensive. We can't accept this," she said hesitantly, trying to return it.
"Don't worry, it's not expensive," Yuuto replied casually.
"Just think of it as a gift from an older brother to his little sisters."
He gently patted Mikan's head while smiling.
"Besides, if you don't want to accept it, I'll just throw it away."
Mikan jolted.
"Eh—don't throw it away!"
"So you have to accept it," Yuuto said, looking at Mikan as he took her hand and put the bracelet on her.
Mikan panicked for a moment, then stepped back slightly, her face growing even redder.
"O-okay…" she finally said, before sitting back down and holding the bracelet tightly.
Yuuto smiled in satisfaction at her reaction. He then stood up from the sofa.
"Well then, I'll be going now," he said casually.
"Remember, contact me if anything happens, and make sure you always wear those bracelets."
Belfast stood up beside Yuuto, adjusting her posture with elegance.
"Eh, you're leaving already?" Riko asked spontaneously.
Yuuto turned to her and smiled faintly.
"Oh? Do you want me to stay longer?" he said casually.
"Sorry, little sister, I still have things to take care of. But don't worry—I'll come by again from time to time."
He gently patted Riko's head.
Riko's face immediately turned red.
"I-it's not like that!" she protested quickly.
Mikan, who had also stood up, stepped forward slightly.
"Y-you… you'll come again, right?" Mikan asked softly, looking at Yuuto with uncertainty.
Yuuto looked at the two of them.
"You don't have to wait for me to come every time," he said casually.
"You're both welcome to come to my apartment anytime."
Mikan and Riko nodded lightly, clearly understanding what he meant.
Yuuto then opened his arms. Belfast immediately wrapped her arms around him without hesitation, and the two of them walked side by side toward the door.
Riko, watching that scene, fell silent, her eyes widening slightly.
"They're… really close," she murmured, her expression gloomy, as if she had lost something.
Mikan turned toward Riko, observing her expression for a moment, then could only let out a soft sigh.
A short while later, Yuuto and Belfast were standing in front of the door. Riko and Mikan walked them out.
"S-see you later, Yu-Yu nii-san," Mikan said nervously, her voice trembling slightly.
Riko froze the moment she heard that, her eyes widening in disbelief at what her younger sister had just said.
"Oh?" Yuuto smiled faintly.
"So you finally acknowledge me as your older brother, huh."
He gently patted Mikan's head, then shifted his gaze toward Riko, a smile forming on his face.
Riko flinched, then quickly turned her face away.
"N-no! I won't say something like that," she retorted quickly, clearly avoiding Yuuto's gaze.
"Heh, you're pretty stubborn," Yuuto said with a smile.
He then waved his hand at the two of them.
"See you later. I'll come again tomorrow."
After that, Yuuto closed the door.
Click.
The door closed, leaving only Mikan and Riko behind.
Mikan slowly turned around, about to head back inside, but her steps stopped when she heard a quiet murmur behind her.
"Nii-san…" Riko whispered.
Mikan turned around.
Riko stood still, her head slightly lowered, her fingers unconsciously touching the bracelet now wrapped around her wrist—the one Yuuto had given her.
---
Yuuto and Belfast soared through the air toward Yuuto's workshop without any obstacles. After a short while, their destination finally came into view.
Whoosh—
The two of them landed smoothly in front of the workshop. Yuuto carefully set Belfast down until her feet touched the ground.
But before he could say anything, a loud shout suddenly rang out from the front of the building.
"Melusine! You finally came—we've been waiting forever!" Honoka shouted as she ran toward Yuuto. Kotori and Umi followed right behind her, their steps quick and full of excitement.
"Sorry," Yuuto said calmly. "I had a few things to take care of first."
As soon as Yuuto stood in front of them, Honoka, Kotori, and Umi immediately surrounded him. They stood far too close—their small hands unconsciously touching his arms, shoulders, and back, as if to make sure he was really there.
"Seriously, you took so long," Kotori muttered.
"Yeah, we even thought you went to another world again," Umi added, staring at Yuuto from close range.
Yuuto chuckled softly, then gently patted their shoulders.
"Relax, I'm here," he said. "Now let's go inside. I still need to continue my training."
Hearing that, they slowly stepped away from Yuuto, though reluctant expressions were still visible on each of their faces.
After that, Belfast calmly wrapped her arm around Yuuto's. Only then did Umi, Kotori, and Honoka notice her presence. All three of their faces immediately turned red as they realized what they had just done.
However, Belfast said nothing—her expression remained calm. She simply stayed at Yuuto's side, walking with him into the warehouse, followed by Umi, Kotori, and Honoka, who were still wrapped in awkward feelings.
A short while later, Yuuto stood alone in the center of the warehouse. Not far from him, Honoka, Kotori, Umi, and Belfast sat atop large roots protruding from the ground.
Yuuto then took out a flip phone and began calling someone.
Seeing this, Belfast turned toward the three girls beside her and whispered softly,
"Don't you… find it strange?" she asked carefully.
"Why is Yu— I mean, Melusine—using a phone to train?"
Honoka spoke up next.
"Well, we thought it was strange at first too," she said with a small smile.
"Why someone like Melusine would have such an old-fashioned phone, and what it was even for."
Kotori continued calmly,
"He said that phone connects him to another world… and to his teacher."
Belfast raised her eyebrow slightly.
"And you just believed that right away?"
Umi responded without hesitation,
"We've seen far too many magical things happen around Melusine," she said seriously.
"And that phone has also released strange objects many times—things that clearly make no sense."
Umi looked straight at Belfast.
"So how could we not believe it?"
Belfast looked at them one by one. She didn't continue speaking, choosing instead to keep her thoughts to herself.
Soon after, Yuuto's voice echoed from the center of the warehouse.
"So, Sensei… what will I be learning now?" Yuuto asked as he called Lady Avalon.
"We will now move on to a higher level," Lady Avalon said.
"This time, you will not be learning ordinary magecraft. You will awaken an ability that you were always destined to possess as a being of Gaia— a foundation that stands at the origin of the very pinnacle of magecraft itself."
She paused briefly, then continued in a meaningful tone.
"That is… Marble Phantasm."