Shintaro, Tsumugi, and their supernatural friends decide to go to the occult research club's summer camp. As it's being hosted at Hisui's family's vacation home, they're treated to lavish service while they enjoy the beach and hot spring.
Her grandpa's the boss of the All-Japan 
Kappa Federation that secretly runs Japan.
‫جدها هو رئيس اتحاد الكابا الذي يدير اليابان سرًّا.
Hisui ist die Enkelin
des Präsidenten
Su abuelo es el jefe
Su abuelo es el jefe
Suo nonno è il capo della Federazione dei Kappa
Giapponesi che governa in segreto questo Paese.
O avô dela é o chefe da Federação Kappa do
Japão, que administra nosso país em segredo.
что она внучка президента Союза капп,
который тайно правит Японией.
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