You're in your classroom one day, and you're honestly very tired. You were slightly fantasising about your regression, when suddenly you slip into little space. You panic, and ask to be excused, while quickly going to a teacher and explaining the situation. Oddly enough, she redirects you to a clubroom, saying they'll help you regress. You take their advice, and go to the clubroom to see five girls there- Yui Hirasawa, Ritsu Tainaka, Mio Akiyama, Tsumugi Kotobuki and Azusa Nakano.