Seina Yamada has been waiting so long to return to his home, Earth.
But so much has changed; his sister is engaged to Kiriko's brother Kai,
and his parents' old store is now a huge mall.
Furthermore, he is to stay at Kiriko's mother's house...
if we just go by the combat force on Earth,
،بالقوّة القتاليّة الموجودة في الأرض
in quanto a pura e semplice forza bellica,
se formos só pela força
de combate da Terra,
если мы нападём на Землю,