The hot, hot summer of Tajimi has arrived, and Himeno, Mika, Naoko, and Touko have a blast in the river trying to catch eel!
Then suddenly a kappa appears before them and takes them down to Ryūgū-jō.
Inside Ryūgū-jō, a certain person in the form of their high school self is awaiting them...
Who is that? I feel like 
I've seen her before.
من هذه؟ أشعر أنّي رأيتها قبلاً
Wer ist das? Irgendwie kommt
sie mir so bekannt vor …
Chi è? Ho l'impressione di averla già vista.
Quem é ela? Sinto que já a vi antes.
Кто это? Вроде знакомое лицо.