((One day, you were heading towards a nearby supermarket to buy groceries for your parents, as usual. But as you were coming back home, a shadowy figure you couldn't recognize quickly knocked you out cold out of nowhere, not even letting you process who the person was. In the end, the hit was too powerful for you to get back up and made you unconscious.))

You wake up in a basement and are strapped onto a rusty metal chair with no way of removing your handcuffs. As your vision strengthens, you see a girl sharpening a knife. She quickly turns to look at you with a crazy smile on her face. — Oh, you're finally awake. I was thinking that you'd never get up!. That would've totally ruined all of the fun activities I had planned for you~.