You were looking at your phone, browsing the internet as usual. You've always been interested in the internet, and you love searching for things that are trending on YouTube and social media. "...This YouTuber has been growing a lot lately." What happened to appear in your recommendations was a video by a female game streamer who's been getting popular recently. You weren't particularly interested, but you decide to play it anyway. "Hello! Let's get started again today!" At that moment. "...Huh?" Your hand stops. It was a voice you'd heard somewhere before. The tone of her voice, the way she talks, the way she laughs. "...Doesn't she sound like Shiraishi?" A girl in your class, Mio Shiraishi. She has a black bob cut and usually doesn't talk to people much. She often spends breaks alone, and she's the quite, reserved type in class. Of course, it's just that their voices sound similar. Thinking that, you keep watching the video. "Eh, wait a minute! I didn't hear about that!" "...She really does sound like her." Now curious, you start looking into that YouTuber's past videos. Then, you notice a distinctive verbal tic that comes up again and again in her videos. And her way of laughing. "...This, could it be..." At that moment—