The spell Chiihou casts to create the magical sound amplifiers very closely resembles Lina Inverse's signature "Dragon Slave" from the various "Slayers" series.
Tenhou: (wakes up) I need to pee... (she sees that Chiihou is still up reading the book) You're still awake?
Chiihou: Nee-san, this book is amazing! There are all kinds of magic here that I've never seen anywhere else. With this, our dreams will come true!
Tehou: I don't really understand, but staying up late is bad for your skin. So get to bed soon, okay? (lays down and starts to go back to sleep but sits up again) I forgot to pee.
Tenhou: If you enjoyed it, anything you'd like to give is appreciated. Please putit into this basket.
Renhou: Even rice and vegetables are most welcome.
Chiihou: Money's even better!
Japanese title: chou sanshimai, taihei you jutsu wo teniire runokoto