English Trophy title: Pardon me!
For this trophy, you will have to visit each of the vocaloids rooms.
In order to be able to access all their rooms, you will have to have played a song with each of the cast members. Either by singing alongside Miku, or choosing them as the first character.
Once that is done, From the main menu press the DIVA option and then you will enter Miku's room. From there, press triangle and at the bottem of the list, you will have to option to switch in between rooms.