Definition of Boyfriend Girlfriend

A meal proceeded in an atmosphere that was relatively quiet but not awkward.

They didn't talk much, only occasionally exchanging brief opinions on the taste of a particular dish.

After eating, Kazehara Tetsu skillfully gathered the dishes and took them to the kitchen to wash.

Sakayanagi Arisu sat back down in her chair, gazing at the deepening night outside the window.

Kazehara Tetsu wiped his hands as he walked out of the kitchen.

"As a boyfriend, what are your thoughts?" Sakayanagi Arisu suddenly spoke, asking a question that made the atmosphere delicate.

Kazehara Tetsu lay down on the bed.

"Thoughts?"

He stared at the ceiling. "It's probably like finally unlocking the final boss of a game, only to find out she can actually be set to 'teammate' mode. Feels pretty novel."

He answered her question in a way they both understood.

"Just 'novel'?"

"Well, there's a bit of accomplishment too."

He turned his head, looking at her profile. "After all, being the one who can make Sakayanagi Arisu say 'I lost'—in this school, it's probably just me."

There was a faint trace of showing off in his words.

Sakayanagi Arisu didn't refute him. She simply turned her head, those violet eyes appearing especially deep under the soft lights.

"What about you? Any thoughts?" Kazehara Tetsu asked back.

"It's a process that requires adaptation."

Sakayanagi Arisu's voice was calm, as if stating an objective fact.

"Then what do you need to adapt to—the title of 'boyfriend,' or the fact that you lost to me?"

"Neither. For me, what needs adapting to is a new variable forcibly inserted into my life. This will add an extra step to every future situation I face."

Kazehara Tetsu chuckled lightly, neither agreeing nor disagreeing with her answer.

"Then before this, did you ever imagine us becoming a couple? Even for a fleeting moment?"

"No."

Sakayanagi Arisu answered cleanly, without any hesitation. "In my predictions, you were just the first 'observation target' in this school worth taking seriously. I envisioned many possible relationships between us—ally, enemy, or... a chess piece recruited under my banner after being defeated. But 'couple' was never an option. It's too... inefficient."

"Inefficient?"

"Yes."

"It generates unnecessary emotions called 'feelings,' which interfere with the most precise judgment."

She deconstructed the relationship of "couple" thoroughly.

Then, she turned the question back on him, those violet eyes carrying a hint of probing inquiry.

"What about you? From when did you start having this 'inefficient' thought about me?"

"Huh... didn't I say it before? Pure lust. If I could turn a proud, unyielding girl into something that belongs only to me, that would be interesting."

Sakayanagi Arisu listened quietly, her expression unchanged.

But the slender fingers resting on her knees unconsciously curled up.

The atmosphere in the room grew subtly tense because of this conversation.

"Since we're already a couple now, we should at least act like one."

Kazehara Tetsu's voice broke the silence, as if he'd suddenly thought of something. "For example, starting tomorrow, let's have lunch together?"

"Is this to announce our relationship to the outside world?"

Sakayanagi Arisu immediately seized on the possible intent behind this action. "By acting together publicly, sending a clear signal to my faction and Katsuragi's faction?"

Kazehara Tetsu looked at her like that and shook his head helplessly.

"Arisu, can you please shut down that brain of yours packed with schemes and calculations for one minute?"

He sat up, got off the bed, and walked over to her.

He leaned down, placing his hands on the armrests of her chair, trapping her between himself and the chair.

"This has nothing to do with factions, signals, or anyone else."

"This is simply me wanting to spend a little more time with you. A boyfriend wanting to have lunch with his girlfriend—that's all. Is that reason 'normal' enough?"

Warm breath washed over her, and Sakayanagi Arisu's body stiffened for a moment.

This was the first time she had been so close, so passively enveloped by a member of the opposite sex.

She could smell the faint scent unique to him, mixed with a masculine aura.

For the first time, her brain experienced a brief, computational lag—a blank.

"...I understand."

After a long pause, she finally found her voice. She tilted her head slightly, avoiding his overly direct gaze. "Since this is part of a couple's daily routine, I have no reason to refuse."

"Very good." Kazehara Tetsu straightened up, a satisfied smile returning to his face.

"Speaking of which, we still have these." He shook the envelope containing the hot spring invitation tickets in front of her.

Sakayanagi Arisu's gaze fell on the two hot spring invitation tickets.

"When do you want to go?"

"Any suggestions, Arisu? The weekend? Or wait for some holiday?"

"The tickets are valid for five months. The nearest holiday is summer vacation."

"In that case, let's go with that."

Sakayanagi Arisu looked at the two tickets printed with hot spring scenery.

Outside the window, the night had already deepened completely.

In the distant buildings, scattered lights began to glow.

"It's getting late."

Kazehara Tetsu glanced at the time on his phone. "If I stay any longer, it might cause unnecessary trouble."

"Mm." Sakayanagi Arisu nodded. She picked up the cane leaning against the edge of the table, supporting herself as she stood.

He walked to the door and pulled it open for her.

Sakayanagi Arisu, leaning on her cane, reached the doorway. Her footsteps paused.

She turned around, looked up, and faced Kazehara Tetsu standing by the door.

"Then, see you tomorrow, Kagihara."

"See you tomorrow, Arisu."

Sakayanagi Arisu did not reply. She simply turned, leaned on her cane, and walked step by step toward the elevator hall.

Kazehara Tetsu did not close the door immediately.

He just leaned against the doorframe, hands in his pockets, quietly watching that small, delicate figure.

Haste makes waste.

For a girl like Sakayanagi Arisu, any impatient advance would only provoke her strongest resistance.

Moreover, to truly earn her recognition, he would have to defeat Ayanokoji Kiyotaka face-to-face, proving his own ability surpassed that of the "genius."

He gently closed the room door. In the room, it seemed a trace of her unique, cool fragrance still lingered.