Natsuki sets his heart on creating a tidal power generator that utilizes the ebb and flow of the ocean's tides. He dives back into the ocean to find some materials and salvages some resin from the ruins of Ryuuji's family's factory. As soon as he gets back he gets to work. As they are working, Natsuki and Ryuuji exchange heated opinions over how the generator should be built. Atri intervenes and the two guys become closer friends. Meanwhile, a suspicious-looking character peeks at them from outside of the school....
Because when we first talked, 
it didn't sound like you'd be any help.
لأنّ عندما تكلّمنا أوّل مرّة، لم تبدُ شخصاً مُفيداً
Weil ich aus unsren Gesprächen nicht
das Gefühl hatte, als würdest du was taugen.
Cuando hablé contigo,
no me pareció que pudieras colaborar.
Cuando hablé contigo,
no me pareció que pudieras colaborar.
Vu ta façon de parler,
j’attendais pas grand-chose de toi.
Dalle nostre conversazioni, non credevo
 ti saresti rivelato una risorsa valida.
Pelas conversas de antes,
Мне казалось,
от тебя не будет никакого толку.
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