Just when you thought the Idolmaster gravure series couldn't get any more shameful, Namco Bandai provided a first look at volume 5 today:
Yes, the special clothing this time is pajamas. With Idolmaster G4U Vol.5, you'll be able to sample what it's like to be with the idols in their room after they've changed into their pajamas.
Volume 5 also includes white swimsuits.
Namco Bandai gives official names to all this stuff. The pajamas are called "Good Sleep Pajamas." The swimwear is called "765 White School Swimwear" (765 is the name of your production studio). The background where you take all the pics this time is called "House Studio."
Take a look at this first video of Good Sleep Pajamas, 765 School Swimwear and House Studio.