Persona 4: Dancing All Night will have a set of special costumes designed by Shuji Sogabe who is working on the Persona 4 manga. These costumes can be obtained by purchasing different Dengeki magazines.
Dengeki PlayStation volume 593 comes with costumes for Yu, Teddie, and Teddie in his human form.
The August issue of Dengeki Maou includes a code to get new outfits for Naoto, Rise, and Kanji.
Yosuke, Chie, and Yukiko costumes are a bonus with Persona Magazine July 2015.
Persona 4: Dancing All Night comes out in Japan tomorrow.