Tadakusa and Yanna visit Sun Beach Nikkogawa, the pool known as the Waikiki Beach of Nagoya. There they find Yatogame completely at the mercy of her cousin Shiharu. For some reason, Shiharu hits it off instantly with Dobe, who just happened to be there as well... With Nanaho and even the teachers at the pool, the atmosphere is peaceful and friendly... but are they forgetting someone?
I'm gonna stay at Mona-nee's place 
for all of summer break!
سأبقى في منزل مونا-نيه 
!طوال العطلة الصيفية
Die ganzen Sommerferien
bleib ich bei Mona!
Je veux rester chez Mona
toutes les vacances d’été !
Starò a casa di Mona-nee
per tutte le vacanze estive!
Vou ficar na casa da Mona 
por todas as férias de verão!
Я осталась у Моны на всё лето.