Different from what Yuu imagined, the interior of the Science classroom hadn't undergone any changes.
"Alright, alright, time to start the lesson~ Students, please quickly take your seats."
Pretending to be serious, Sora stepped into the classroom with steps that somehow felt light, took out her wand and waved it twice. All desks and chairs immediately moved backward to the back of the class, leaving only one chair right in front of the blackboard.
She then walked to the podium, snapped her fingers gracefully, making the projector screen slowly descend, and the lights dimmed. Everything looked as if about to play an educational documentary slide film.
After completing all that, Sora nodded satisfied.
"You're quite enjoying your game..." Yuu behind commented wordlessly.
As if not hearing his words, Sora sank into her own thoughts while holding her chin, "Hmm... One and a half hours left before the cycle starts. Should be enough for me to explain everything."
"Even the contents of a novel of several thousand words can be finished telling in one and a half hours."
Was the past story that massive?
Bringing doubt and curiosity, Yuu naturally sat on that chair, right in front of the Adult Little Sister wearing a lab coat.
"Although it's not finished today, you should be able to continue after the next cycle starts. Or as administrator will you also lose memories because of the cycle?"
"Shouldn't..." Sora hesitated, as if there was something difficult to express, but quickly she decided not to explain.
"Well, I'll try to tell it briefly."
With hands in her lab coat pockets, Sora sighed long while lowering her small face, "Actually, I planned to only reveal the truth in front of you after everything ended... Unfortunately, too many unexpected things happened this time, causing my plan to basically fail totally like waste paper. Now, I can only see and take the next step."
She raised her eyes, her helpless yet gentle gaze staring at the brother before her. That gaze was like looking at cherry blossoms that hadn't withered in summer, yet also filled with unspoken hope.
"What can be done, Yuu is the troublesome type who finds it hard to act without understanding the current situation. Since everything has happened, I can only tell you this entire incident first, then let you complete the trial."
Yuu returned her gaze. His expression was calm and steady. He pursed his lips slightly, signaling for her to start speaking.
"In that case..."
Sora sighed softly, then took out her wand again from her sleeve, pointed it at the imageless projector screen, and briefly exclaimed:
"Manifest Memory!"
Familiar snowflakes suddenly appeared, and the image on the screen slowly became clear amid the shaking.
Yuu stared at her confusedly, "Is there such a spell in Harry P○tter?"
"There isn't." Sora said without changing expression, her pale eyes narrowing slightly, "I just shouted the spell to look more energetic. Do you object?"
"No, of course not."
"Hmph~"
That slightly dissatisfied yet somehow proud-sounding snort was cute like a cat making mischief and naturally asking its master to scratch its chin.
Although not the same person, Yuu confirmed again in his heart—no matter in which world, Sora remained the little sister he knew and cherished.
"Ahem, before we officially start, let me confirm something."
Her wand tapped her slender white palm. At some point Sora had worn thin-framed glasses, radiating an intellectual and mature Onee-san aura like a young female teacher.
"Yuu, do you want to know from the beginning part, or do you want to hear my own experience first?"
Yuu furrowed his brow slightly.
"What's the difference between the two?"
"Of course there is."
Sora smiled faintly, speaking in a relaxed tone as if discussing what game she just played today, "I only went through dozens of world lines to arrive here, while the origin of everything... According to Kanade, that happened about hundreds of world lines ago."
"..."
Unable to say a single word, Yuu stared at her shocked.
After a long time, he finally repeated the question in a disbelieving tone, "Hundreds of world lines?"
Not a few days, not a few years... But hundreds of world lines?
Was the time unit problematic?
"Don't doubt, indeed world lines."
Sora spread her hands and shrugged, not surprised by his reaction.
"However, when my turn arrived, my consciousness would definitely awaken on some day when you were seventeen years old, then at most less than three years, I would shift to the next world line to keep trying. So, the total time I experienced wasn't too long."
(So, your current age is 16+3X years?)
Ignoring thoughts to investigate the doubts within, and also suppressing instinct to mock the above sentence, Yuu unconsciously pressed his temple with his thumb. Looking headache-stricken, he asked:
"Then why, Kanade you mentioned... namely Tachibana Kanade? Could know such things..."
He himself vaguely suspected the reason, yet felt it impossible and instinctively denied it.
Anyway, if indeed like that, referring to Sora's experience, the person named Kanade...
Wasn't she the same as having experienced hundreds of years of time?
"Because she's the person concerned."
However, in the next second, the little sister from another world with a too-relaxed tone confirmed that cruel reality.
"Besides things I experienced, everything that happened to you in all world lines, everything she witnessed hundreds of times... everything was told directly by Kanade to me."
"Although you no longer remember, the origin of all stories until now, started from your two's meeting."
Ignoring Yuu's dazed expression that hadn't recovered, Sora looked at the projector screen. The messy snowflakes had disappeared, replaced by a documentary-like video.
Because the system had automatic recording functions, this video was taken from a third-person perspective—this function was also told to her by Kanade. When explaining the ins and outs, she often used these videos to help her explanations.
Anyway, watching films was always more impressive and striking than listening to stories. It also saved effort telling from the beginning.
"Watch carefully, Yuu."
"That's the starting point of the first world line, the origin of everything. Also the reason why we were determined without regret, no matter how many world lines must be traversed, no matter how long we must wander in the river of time, we must change fate for your sake—"
"The beginning of the story."
◆━⊰✧⊱━◆
Summer.
That was a very ordinary afternoon.
An ordinary youth met an extraordinary system, and started an extraordinary life.
The youth's name was Tenkuji Yuu.
The system's name was Girlfriend Development System.
He knew what he had to do. All plans were clear in his mind. Everything was ready, just waiting for the right moment.
Right, Yuu still lacked one girlfriend.