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....
Don't you move! I'm sure 
you don't want to get hurt.
ولا حركة! أنا متأكّدة بأنّك
لا تريدها أن تتأذّى
Keine Bewegung!
Oder ich muss ihr leider wehtun.
No te muevas
si sabes lo que te conviene.
No te muevas
si sabes lo que te conviene.
Plus un geste,
ou ça va très mal finir pour elle.
Non muovetevi! 
Non vorrete che le succeda qualcosa di brutto!
Ninguém se mexe! Não queremos
que a mocinha se machuque.
Не дёргайся, если тебе её жизнь дорога!
อย่าขยับนะ