The girls are running in their exercise outfits, with the boobs swaying to and fro. Arata's heart races. Everyone's having great time, and then a ghost appears in the library. Arata and the gang go to check it out, and are forcefully transported to the "Eternal Library". There they find the lost Trinity Seven!
I can't just sit around after hearing 
that we're fighting over Onii-san.
Wenn man sich über Onii-san streitet,
dann kann ich nicht tatenlos zusehen.
Ya que pelearemos por Arata, 
no puedo contenerme.
No puedo contenerme si peleamos por Arata.
Je ne peux pas
juste vous regarder
Non posso stare a guardare sapendo 
che state combattendo per l'Onii-san.
Eu não vou me segurar já 
que vamos brigar pelo Onii-san.