Toward the end of chapter 55, Kasuga is in his apartment. He opens up a notebook and it's blank. Tokiwa shows up and asks him about the notebook. Kasuga says, "I haven't written anything in it, yet." Tokiwa responds, "What are you going to write?" Kasuga says, "I don't know yet.". Tokiwa spends the night, they make love and fall asleep. This leads right into chapter 56...