When I woke up, I was staring at an unfamiliar ceiling. 　No, not just the ceiling. The walls, the angle of the light coming through the window — everything was different from any morning I'd experienced in my thirty-seven years of life. Yuki sat up. His body felt strangely light. "……Huh?" 　The voice that escaped his lips wasn't his own. It was younger, the voice of someone around high school age. 　He looked around frantically. An unfamiliar room. What looked like a school uniform hung over a chair. On the desk sat textbooks and a planner. 　He opened the planner. A student ID was tucked inside the front cover. The photo showed a young man he didn't recognize. The name read "Yuki." Kouyou Academy, Class 2-C. "Yuki……?" 　Was that his name? No. His name was Yuki, but this wasn't his face. This wasn't his body. 　He searched for a mirror. The small mirror in the washroom reflected a young man with short black hair. Deep brown eyes stared back, wide with shock. (Was my face always like this……?) 　No. Absolutely not. 　This wasn't the face he'd lived with for thirty-seven years. Where had that slightly tired, middle-aged face with wrinkles at the corners of his eyes disappeared to? 　He reread the planner. The address field said "3-7-202 Oka no Ue, Minakaze City." Minakaze City. A place name he'd never heard before. 　He looked out the window. An unfamiliar townscape stretched before him. In the distance, he could see the ocean. A peaceful view facing the Pacific. But this wasn't the city he knew. (A parallel world……?) 　The ridiculous-sounding phrase surfaced in his mind. But he couldn't think of any other explanation. 　It seemed that Yuki, a thirty-seven-year-old single middle-aged man, had suddenly, as of this morning, possessed the body of a high school student named Yuki in this world. 　A way to return to his original world? He had absolutely no idea. 　Why had this even happened in the first place? He didn't even know the cause. 　Yuki sat down on the bed and let out a sigh. "[sad]……What am I supposed to do?" 　But he couldn't just hole up in this room forever. 　First, he had to avoid giving himself away and live a peaceful school life as this world's Yuki. That was his immediate goal. (Peacefully. Just peacefully, above all else.) 　Chanting that in his mind, Yuki slipped his arms through the sleeves of his uniform. 　Kouyou Academy. 　Passing through the main gate, a school building with white walls came into view. A three-story main building, and a four-story special wing further back. Ginkgo trees lined the spacious schoolyard. 　It was a far more impressive academy than he'd imagined. 　The classroom for Class 2-C was at the east end of the main building's second floor. The moment Yuki entered, a stir instantly spread through the room. "Ah, it's the transfer student, Yuki-kun." "I heard he's sitting next to me." "He's pretty good-looking, isn't he?" 　The classroom was mostly filled with female students. 　Including himself, there were only three boys. (Somehow, there are an awful lot of girls here……) 　And that wasn't all. Everyone's gazes felt strangely intense. They were looking at him like he was some kind of rare creature. 　Guided by his homeroom teacher, an older woman, he took his seat by the window. And in the seat next to him was—. 　Glistening, waist-length, straight blonde hair. 　Large blue eyes were fixed intently on Yuki. 　A small, pale face. Every gesture exuded refinement. "My name is Shiratori Mio." 　A soft, gentle voice. Her refined way of speaking was strangely pleasant to the ear. "[gentle]I look forward to getting to know you, Yuki-kun." 　Mio smiled. That smile was so pure, without a single cloud in it. 　For a moment, Yuki was at a loss for words. 　His young body's heart gave a loud thump. (Calm down. Inside, you're thirty-seven.) 　He told himself that. He had to handle this with an adult's composure. "[serious]……Nice to meet you." 　He gave a short reply. That was all he could manage. 　Mio nodded happily and took out her notebook. Every single one of her movements seemed somehow incredibly graceful. 　As Yuki opened his textbook, he glanced at his neighbor. 　Mio was already in a posture of listening to the teacher. But he had a feeling she was glancing his way from time to time. 　When their eyes met, she smiled at him again. (What is this strange feeling……?) 　How could I, a thirty-seven-year-old used to women, get this flustered over a single high school girl? (Is it because this body is young after all?) 　Anyway, he had to do something about this restless atmosphere. For the sake of a peaceful school life—. 　Lunch break. 　Right after the chime rang, Yuki witnessed a shocking scene. 　Mio was standing in front of his desk. 　Her steps were light, as natural as if she'd come to invite him to tea. But her blue eyes were dead serious. "[serious]Yuki-kun." 　The entire classroom fell silent. 　Mio straightened her back perfectly and clasped her hands in front of her chest. "I, Shiratori Mio, wish to enter into a relationship with Yuki-kun!" 　The classroom erupted. "Eeeh!?" "Mio did it!" "Isn't that way too soon!" "But she's serious!" 　Yuki froze. (A relationship? Out of nowhere? On the lunch break of my first day as a transfer student?) 　The adult inside him tried to open his mouth. To gently refuse, with an adult's tact—. 　But his teenage body wouldn't listen. His face flushed hot, and the words stuck in his throat. "[surprised]U-Um……" 　The end of his sentence trembled. Damn it, this isn't my voice. 　Mio hadn't finished speaking yet. "Therefore, I shall be submitting a Kokuri Notification!" 　Kokuri Notification—? 　Yuki's thoughts ground to a halt at this unfamiliar term. 　The surrounding girls stirred even more. "A Kokuri Notification is that thing, right? The one you submit to the municipality." "Don't you need a guarantor?" "It costs 3,000 en, right?" "Mio's serious……" 　Yuki somehow managed to open his mouth. "[scared]W-Wait, hold on." 　Mio tilted her head. That gesture, too, was innocently cute. "[gentle]Whatever is the matter?" "A Kokuri Notification…… what is that?" 　The moment he asked, he realized he'd messed up. It might be common knowledge in this world. 　But Mio didn't seem to mind at all and began explaining politely. "It is a system where a woman, when she is serious about courting a man, files a notification with the municipality. It requires one guarantor and a fee of 3,000 en, but I have already asked my grandmother, Misa, to act as guarantor." 　Kokuri. Not just a confession, but a formal notification. 　A woman—to a man—filed with the municipality. 　In Yuki's mind, the situation slowly pieced itself together. (So that's how it is in this world.) 　The girls are the assertive ones. Confessions all come from the girls. A concrete system of this Chastity Reversal society was now right in front of his eyes. 　He shuddered. 　A peaceful school life? Goodbye to that. "[scared]U-Um, Mio-san." "Mio is fine." "Mio……-san, please, just wait a moment." 　It was the strongest protest he could muster. 　Mio tilted her head again, but after thinking for a moment, she nodded obediently. "[gentle]……I understand. However, I will most certainly submit the Kokuri Notification." 　Saying that, she returned to her own seat. 　The gazes of everyone in the classroom were still piercing Yuki. He could hear the girls whispering. "Mio submitting a Kokuri Notification is pretty big news." "Students from other classes will be interested too." "The transfer student seems to have it rough……" 　Yuki slumped over his desk. 　His head was spinning. (A peaceful school life…… ended on the first day.) 　After school. 　When Yuki fled into the hallway, Mio immediately chased after him. 　She led him to a corner of the main building's second floor. In front of the door was a plate reading "Yasuragi Room." It seemed to be a rest room exclusively for male students. "I am serious." 　Mio stood before Yuki, looking up at him with upturned eyes. Her blue eyes sparkled in the evening sunlight. "The Kokuri Notification is proof of my sincerity. I want to be with Yuki-kun and make Yuki-kun happy." 　Such direct words. Pure, without a single cloud. 　He couldn't sense any lies or calculation in them. 　Yuki felt his young body blushing again. His heart was annoyingly loud. (This is bad. This body is too honest.) 　If it were the adult me, I could handle this better. 　Honestly, I should be able to say something like, "I'm happy about your feelings, but I've only just transferred in……" right here. 　But—. "[scared]P-Please wait. Really." 　His voice was that of a young man again. 　Mio gazed intently at Yuki, and then, she smiled softly. "[gentle]I understand. But I will simply wait. My feelings will not change." 　Saying that, she gave a light bow and left. 　Yuki leaned against the wall of the Yasuragi Room. 　The evening sun cast long shadows in the hallway. 　Wind blew in through the window, swaying the curtains. 　In the distance, he could hear the voices of students going home. 　From the very first day, the rumor was probably already spreading throughout the academy. That Mio was submitting a Kokuri Notification for the transfer student—. 　What would happen now? How would the other girls act? 　Peace was nothing more than a distant dream. 　Yuki held his head in his hands and let out a single sigh. 　Through the window at the end of the hallway, he could see the townscape of Minakaze City and the Pacific Ocean beyond. The sea was slowly fading into twilight.