I just clicked! At 3:05 When each group were doing a pose, I thought they were just doing random cute poses but they are actually creating the first letter of their groups name with their bodies! For example Morning Musume made a 'M' , and Berryz made a 'B' etc.
J'ai pas compris grand chose, d’ailleurs, je ne sais toujours pas comment j'ai fait pour arriver sur cette vidéo mais je me suis bien amusez gg et vive le Japon !!! :p